CVE-2026-20093 — This repository contains a proof-of-concept (PoC) exploit for CVE-2026-20093, a critical…

Key facts

CVE-2026-20093 is a Critical (9.8) vulnerability: This repository contains a proof-of-concept (PoC) exploit for CVE-2026-20093, a critical…. This entry ships ready-to-deploy detection and prevention rules (Snort, YARA, Nginx, Apache) plus a detection-only PoC and a Docker test lab.

CVE	CVE-2026-20093
Severity	Critical (9.8)
Detection / prevention	Snort, YARA, Nginx, Apache
PoC	poc.py
Source	2026/CVE-2026-20093/

Details

CVE-2026-20093 is a Critical (9.8) vulnerability: This repository contains a proof-of-concept (PoC) exploit for CVE-2026-20093, a critical…. This entry ships a detection-only proof-of-concept (PoC), a Docker test lab, and ready-to-deploy detection and prevention rules (Snort, YARA, Nginx, Apache) — see Detection and prevention below. Source: NVD record.

English | 한국어

Description

This repository contains a proof-of-concept (PoC) exploit for CVE-2026-20093, a critical authentication bypass vulnerability affecting Cisco Integrated Management Controller (IMC). The vulnerability allows unauthenticated remote attackers to reset any user password, including administrator accounts, by sending crafted HTTP POST requests that bypass authorization checks.

Vulnerability Details

Field	Value
CVE ID	CVE-2026-20093
CVSS Score	9.8 (Critical)
CWE	CWE-287 (Improper Authentication)
Vulnerability Type	Authentication Bypass
Affected Products	Cisco Integrated Management Controller (IMC)
Affected Versions	UCS C-Series, ENCS 5000, Catalyst 8300 (before fix)
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None
User Interaction	None
Impact	Complete hardware-level control of UCS servers

Usage

# Check if target is vulnerable
python3 poc.py --target <url> --check

# Exploit the vulnerability to reset admin password
python3 poc.py --target <url> --verbose

# Example
python3 poc.py --target https://192.168.1.100 --check
python3 poc.py --target https://10.0.0.50 --verbose

Test Environment

docker-compose up -d

This will set up a vulnerable Cisco IMC simulation environment for testing purposes.

Prevention

See prevention/ directory for: - Firmware update instructions - Network segmentation recommendations - Monitoring and detection rules - Mitigation strategies

Disclaimer

This proof-of-concept is provided for educational and authorized security testing purposes only. The author is not responsible for any misuse or damage caused by this code. Only use this tool against systems you own or have explicit written permission to test. Unauthorized access to computer systems is illegal and unethical.

WARNING: This vulnerability provides complete hardware-level access to affected Cisco UCS servers. Exercise extreme caution when testing and ensure proper authorization before use.

Detection and prevention

Ready-to-deploy defensive rules for CVE-2026-20093, for authorized testing and blue-team detection engineering:

• Snort IDS signature — prevention/snort.rules
• YARA detection rule — prevention/yara.yar
• Nginx mitigation — prevention/nginx.conf
• Apache HTTPD mitigation — prevention/httpd.conf
• Detection-only PoC — poc.py
• Rule notes — prevention/README.md

References: NVD — CVE-2026-20093 · full write-up on the searchable site

Detection & prevention rules

Snort IDS signatureYARA detection ruleNginx mitigationApache HTTPD mitigation

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass Attempt - /imc endpoint"; flow:established,to_server; content:"GET"; http_method; content:"/imc"; http_uri; depth:4; content:!"Authorization:"; http_header; content:!"Cookie:"; http_header; classtype:web-application-attack; sid:20260001; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass Attempt - /redfish/v1 endpoint"; flow:established,to_server; content:"GET"; http_method; content:"/redfish/v1"; http_uri; depth:10; content:!"Authorization:"; http_header; content:!"Cookie:"; http_header; classtype:web-application-attack; sid:20260002; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass Attempt - /xmlapi endpoint"; flow:established,to_server; content:"POST"; http_method; content:"/xmlapi"; http_uri; depth:7; content:!"Authorization:"; http_header; content:!"Cookie:"; http_header; classtype:web-application-attack; sid:20260003; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - Administrative access without credentials"; flow:established,to_server; content:"/imc"; http_uri; content:"admin"; http_uri; content:!"Authorization:"; http_header; classtype:web-application-attack; sid:20260004; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - Redfish system access"; flow:established,to_server; content:"/redfish/v1/Systems"; http_uri; content:!"Authorization:"; http_header; classtype:web-application-attack; sid:20260005; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - Redfish managers access"; flow:established,to_server; content:"/redfish/v1/Managers"; http_uri; content:!"Authorization:"; http_header; classtype:web-application-attack; sid:20260006; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - XML API configuration"; flow:established,to_server; content:"POST"; http_method; content:"/xmlapi"; http_uri; content:"configConfMo"; http_client_body; content:!"aaaLogin"; http_client_body; classtype:web-application-attack; sid:20260007; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - IMC login bypass attempt"; flow:established,to_server; content:"/imc/login"; http_uri; content:"bypass"; http_uri; nocase; classtype:web-application-attack; sid:20260008; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - User management access"; flow:established,to_server; content:"/imc/user"; http_uri; content:!"Authorization:"; http_header; classtype:web-application-attack; sid:20260009; metadata:cve CVE-2026-20093; rev:1;)

alert tcp any any -> any [80,443] (msg:"CVE-2026-20093 Cisco IMC Authentication Bypass - Privilege escalation attempt"; flow:established,to_server; content:"PUT"; http_method; content:"/redfish/v1/AccountService/Accounts"; http_uri; content:!"Authorization:"; http_header; classtype:web-application-attack; sid:20260010; metadata:cve CVE-2026-20093; rev:1;)

:material-file-download: prevention/snort.rules

```yara
rule CVE_2026_20093_Network_Traffic_Auth_Bypass
{
    meta:
        description = "Detects network traffic patterns for CVE-2026-20093 authentication bypass in Cisco IMC"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "high"
        cve = "CVE-2026-20093"

    strings:
        $endpoint1 = "/imc" nocase
        $endpoint2 = "/redfish/v1" nocase
        $endpoint3 = "/xmlapi" nocase

        $bypass1 = "X-Auth-Token:" nocase
        $bypass2 = "Authorization: Bearer" nocase
        $bypass3 = "Cookie: token=" nocase
        $bypass4 = "X-Forwarded-For:" nocase
        $bypass5 = "X-Real-IP:" nocase

        $method1 = "POST" nocase
        $method2 = "PUT" nocase
        $method3 = "DELETE" nocase

        $payload1 = "sessionId=" nocase
        $payload2 = "authCookie=" nocase
        $payload3 = "csrf_token=" nocase
        $payload4 = "<configConfMo" nocase
        $payload5 = "<aaaLogin" nocase

        $suspicious1 = "../" nocase
        $suspicious2 = "%2e%2e%2f" nocase
        $suspicious3 = "admin" nocase
        $suspicious4 = "root" nocase

    condition:
        any of ($endpoint*) and 
        (any of ($method*) and any of ($bypass*)) and
        (any of ($payload*) or any of ($suspicious*))
}

rule CVE_2026_20093_Exploit_Payload_Detection
{
    meta:
        description = "Detects exploit payloads targeting CVE-2026-20093 authentication bypass"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "critical"
        cve = "CVE-2026-20093"

    strings:
        $xml_payload1 = "<aaaLogin inName=\"\" inPassword=\"\"" nocase
        $xml_payload2 = "<configConfMo inHierarchical=\"false\"" nocase
        $xml_payload3 = "<aaaRefresh inName=\"\" inPassword=\"\"" nocase
        $xml_payload4 = "<aaaLogout inCookie=\"\"" nocase

        $json_payload1 = "{\"UserName\":\"\",\"Password\":\"\"}" nocase
        $json_payload2 = "{\"SessionId\":\"" nocase
        $json_payload3 = "\"@odata.id\":\"/redfish/v1/SessionService/Sessions" nocase

        $exploit_pattern1 = "inCookie=\"\"" nocase
        $exploit_pattern2 = "cookie=null" nocase
        $exploit_pattern3 = "token=undefined" nocase
        $exploit_pattern4 = "sessionId=0" nocase
        $exploit_pattern5 = "authToken=\"\"" nocase

        $privilege_escalation1 = "privilege=\"admin\"" nocase
        $privilege_escalation2 = "role=\"Administrator\"" nocase
        $privilege_escalation3 = "priv=\"15\"" nocase

        $command_injection1 = ";<" nocase
        $command_injection2 = "|sh" nocase
        $command_injection3 = "$(cat" nocase
        $command_injection4 = "`whoami`" nocase

    condition:
        (any of ($xml_payload*) or any of ($json_payload*)) and
        any of ($exploit_pattern*) and
        (any of ($privilege_escalation*) or any of ($command_injection*))
}

rule CVE_2026_20093_HTTP_Header_Manipulation
{
    meta:
        description = "Detects HTTP header manipulation for CVE-2026-20093 bypass attempts"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "medium"
        cve = "CVE-2026-20093"

    strings:
        $header_bypass1 = "X-Forwarded-Host: localhost" nocase
        $header_bypass2 = "X-Original-URL:" nocase
        $header_bypass3 = "X-Rewrite-URL:" nocase
        $header_bypass4 = "Host: 127.0.0.1" nocase
        $header_bypass5 = "X-Forwarded-Proto: https" nocase

        $user_agent1 = "User-Agent: IMCExploit" nocase
        $user_agent2 = "User-Agent: CiscoBypass" nocase
        $user_agent3 = "User-Agent: AuthBypass" nocase

        $custom_headers1 = "X-Admin-Override: true" nocase
        $custom_headers2 = "X-Auth-Skip: 1" nocase
        $custom_headers3 = "X-Bypass-Auth: yes" nocase
        $custom_headers4 = "X-Internal-Request: true" nocase

        $referer_bypass1 = "Referer: https://localhost/imc" nocase
        $referer_bypass2 = "Referer: https://127.0.0.1/redfish" nocase

    condition:
        (any of ($header_bypass*) or any of ($custom_headers*)) and
        (any of ($user_agent*) or any of ($referer_bypass*))
}

rule CVE_2026_20093_Log_Entry_Patterns
{
    meta:
        description = "Detects suspicious log entries indicating CVE-2026-20093 exploitation attempts"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "high"
        cve = "CVE-2026-20093"

    strings:
        $cisco_imc_log = "CISCO-IMC" nocase
        $auth_fail1 = "Authentication failed" nocase
        $auth_fail2 = "Invalid session" nocase
        $auth_fail3 = "Session expired" nocase
        $auth_fail4 = "Unauthorized access" nocase

        $bypass_attempt1 = "Login bypass attempt" nocase
        $bypass_attempt2 = "Session hijack" nocase
        $bypass_attempt3 = "Cookie manipulation" nocase
        $bypass_attempt4 = "Token forgery" nocase

        $endpoint_access1 = "GET /imc" nocase
        $endpoint_access2 = "POST /redfish/v1" nocase
        $endpoint_access3 = "PUT /xmlapi" nocase

        $error_codes1 = "Error 401" nocase
        $error_codes2 = "Error 403" nocase
        $error_codes3 = "Error 500" nocase

        $ip_pattern = /\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/

        $timestamp = /\d{4}-\d{2}-\d{2}[T ]\d{2}:\d{2}:\d{2}/

    condition:
        $cisco_imc_log and 
        (any of ($auth_fail*) or any of ($bypass_attempt*)) and
        any of ($endpoint_access*) and
        $ip_pattern and $timestamp
}

rule CVE_2026_20093_XML_API_Exploitation
{
    meta:
        description = "Detects XML API exploitation patterns for CVE-2026-20093"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "high"
        cve = "CVE-2026-20093"

    strings:
        $xml_header = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" nocase

        $malformed_xml1 = "<aaaLogin inName=\"admin\" inPassword=\"\"></aaaLogin>" nocase
        $malformed_xml2 = "<configResolveClass cookie=\"\" inHierarchical=\"false\"" nocase
        $malformed_xml3 = "<configScope cookie=\"\" inHierarchical=\"true\"" nocase

        $dangerous_methods1 = "<configConfMo cookie=\"\"" nocase
        $dangerous_methods2 = "<configResolveParent cookie=\"\"" nocase
        $dangerous_methods3 = "<lsClone" nocase
        $dangerous_methods4 = "<orgOrg" nocase

        $xxe_attempt1 = "<!ENTITY" nocase
        $xxe_attempt2 = "SYSTEM \"file://" nocase
        $xxe_attempt3 = "<!DOCTYPE" nocase

        $xpath_injection1 = "' or '1'='1" nocase
        $xpath_injection2 = "\" or \"1\"=\"1" nocase
        $xpath_injection3 = "/*[" nocase

    condition:
        $xml_header and
        (any of ($malformed_xml*) or any of ($dangerous_methods*)) and
        (any of ($xxe_attempt*) or any of ($xpath_injection*))
}

rule CVE_2026_20093_Redfish_API_Abuse
{
    meta:
        description = "Detects Redfish API abuse patterns for CVE-2026-20093"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "medium"
        cve = "CVE-2026-20093"

    strings:
        $redfish_path1 = "/redfish/v1/SessionService/Sessions" nocase
        $redfish_path2 = "/redfish/v1/AccountService/Accounts" nocase
        $redfish_path3 = "/redfish/v1/Managers" nocase
        $redfish_path4 = "/redfish/v1/Systems" nocase

        $json_exploit1 = "{\"UserName\":null,\"Password\":null}" nocase
        $json_exploit2 = "{\"UserName\":\"\",\"Password\":\"\"}" nocase
        $json_exploit3 = "{\"SessionId\":\"../../../\"}" nocase

        $odata_manipulation1 = "\"@odata.type\":\"#Session.v1_0_0.Session\"" nocase
        $odata_manipulation2 = "\"@odata.id\":\"../\"" nocase
        $odata_manipulation3 = "\"@odata.context\":\"/redfish/v1/$metadata\"" nocase

        $http_method_override1 = "X-HTTP-Method-Override: DELETE" nocase
        $http_method_override2 = "X-HTTP-Method-Override: PUT" nocase
        $http_method_override3 = "X-HTTP-Method: PATCH" nocase

        $privilege_fields1 = "\"RoleId\":\"Administrator\"" nocase
        $privilege_fields2 = "\"Enabled\":true" nocase
        $privilege_fields3 = "\"Locked\":false" nocase

    condition:
        any of ($redfish_path*) and
        (any of ($json_exploit*) or any of ($odata_manipulation*)) and
        (any of ($http_method_override*) or any of ($privilege_fields*))
}

rule CVE_2026_20093_Session_Token_Manipulation
{
    meta:
        description = "Detects session token manipulation attempts for CVE-2026-20093"
        author = "Security Analyst"
        date = "2024-01-01"
        severity = "high"
        cve = "CVE-2026-20093"

    strings:
        $token_patterns1 = /token=[0-9A-Fa-f]{32}/
        $token_patterns2 = /sessionId=[0-9A-Fa-f]{16}/
        $token_patterns3 = /cookie=[A-Za-z0-9+\/]{40}/

        $malformed_tokens1 = "token=null" nocase
        $malformed_tokens2 = "token=undefined" nocase
        $malformed_tokens3 = "token=0" nocase
        $malformed_tokens4 = "sessionId=" nocase
        $malformed_tokens5 = "cookie=\"\"" nocase

        $replay_indicators1 = "X-Csrf-Token:" nocase
        $replay_indicators2 = "X-Session-Token:" nocase
        $replay_indicators3 = "Authorization: Token" nocase

        $timing_attack1 = /sleep\(\d+\)/
        $timing_attack2 = /setTimeout\(\d+\)/
        $timing_attack3 = "benchmark(" nocase

        $brute_force1 = /token=[0]{32}/
        $brute_force2 = /token=[1]{32}/
        $brute_force3 = /sessionId=[0-9]{1,8}/

    condition:
        (any of ($token_patterns*) and any of ($malformed_tokens*)) or
        (any of ($replay_indicators*) and (any of ($timing_attack*) or any of ($brute_force*)))
}

```

:material-file-download: prevention/yara.yar

# CVE-2026-20093 - Prevention Rules for Nginx
# Authentication Bypass Protection for Cisco IMC

# Rate limiting zones
limit_req_zone $binary_remote_addr zone=imc_auth:10m rate=5r/m;
limit_req_zone $binary_remote_addr zone=imc_api:10m rate=10r/m;

# Map for blocking suspicious patterns
map $request_uri $block_auth_bypass {
    default 0;
    "~*(/imc|/redfish|/xmlapi).*(\.\./|\.\.\\|%2e%2e)" 1;
    "~*(/imc|/redfish|/xmlapi).*(select|union|insert|drop|delete)" 1;
    "~*(admin|root|administrator).*bypass" 1;
    "~*auth.*=.*null" 1;
    "~*session.*=.*(\'\"|null|undefined)" 1;
}

# Cisco IMC Management Interface
location /imc {
    limit_req zone=imc_auth burst=3 nodelay;

    if ($block_auth_bypass = 1) {
        return 403;
    }

    # Block requests without proper authentication headers
    if ($http_authorization = "") {
        return 401;
    }

    # Block suspicious user agents
    if ($http_user_agent ~* (curl|wget|python|scanner|bot)) {
        return 403;
    }

    # Require valid Content-Type for POST requests
    if ($request_method = POST) {
        set $valid_content_type 0;
        if ($content_type ~* "application/(json|xml|x-www-form-urlencoded)") {
            set $valid_content_type 1;
        }
        if ($valid_content_type = 0) {
            return 415;
        }
    }

    # Block requests with malicious headers
    if ($http_x_forwarded_for ~* (127\.0\.0\.1|localhost|::1)) {
        return 403;
    }

    # Validate request body size
    client_max_body_size 1M;

    proxy_pass http://backend;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

# Redfish API Endpoint
location /redfish/v1 {
    limit_req zone=imc_api burst=5 nodelay;

    if ($block_auth_bypass = 1) {
        return 403;
    }

    # Enforce authentication for all Redfish endpoints
    if ($http_authorization = "") {
        return 401;
    }

    # Block invalid HTTP methods
    if ($request_method !~ ^(GET|POST|PATCH|PUT|DELETE)$) {
        return 405;
    }

    # Validate JSON Content-Type for modification requests
    if ($request_method ~* ^(POST|PATCH|PUT)$) {
        if ($content_type !~* "application/json") {
            return 415;
        }
    }

    # Block requests with suspicious query parameters
    if ($query_string ~* (script|javascript|vbscript|onload|onerror)) {
        return 403;
    }

    # Validate session tokens
    if ($http_x_auth_token ~* (null|undefined|admin|root|guest|\'\')) {
        return 403;
    }

    # Block directory traversal in API paths
    if ($uri ~* "\.\.") {
        return 403;
    }

    proxy_pass http://backend;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

# XML API Endpoint
location /xmlapi {
    limit_req zone=imc_api burst=3 nodelay;

    if ($block_auth_bypass = 1) {
        return 403;
    }

    # Enforce authentication
    if ($http_authorization = "") {
        return 401;
    }

    # Only allow POST requests for XML API
    if ($request_method != POST) {
        return 405;
    }

    # Validate XML Content-Type
    if ($content_type !~* "(application|text)/(xml|soap)") {
        return 415;
    }

    # Block XML injection patterns
    if ($request_body ~* "(<script|javascript:|vbscript:|<!ENTITY|SYSTEM|PUBLIC)") {
        return 403;
    }

    # Block XML external entity references
    if ($request_body ~* "(ENTITY.*http|ENTITY.*ftp|ENTITY.*file:)") {
        return 403;
    }

    # Validate session credentials in XML
    if ($request_body ~* "(sessionId|cookie).*=.*(\'\"|null|undefined)") {
        return 403;
    }

    # Limit XML body size
    client_max_body_size 512K;

    proxy_pass http://backend;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

# Global security headers for all Cisco IMC endpoints
location ~* ^/(imc|redfish|xmlapi) {
    add_header X-Frame-Options DENY always;
    add_header X-Content-Type-Options nosniff always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
    add_header Cache-Control "no-cache, no-store, must-revalidate" always;
    add_header Pragma "no-cache" always;
}

:material-file-download: prevention/nginx.conf

# CVE-2026-20093 - Prevention Rules for Apache httpd
# Authentication Bypass Protection for Cisco Integrated Management Controller (IMC)

SecRuleEngine On

# Block unauthenticated access to IMC management interface
SecRule REQUEST_URI "@beginsWith /imc" \
    "id:202620093001,\
    phase:1,\
    block,\
    msg:'CVE-2026-20093: Potential authentication bypass attempt on IMC interface',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:CRITICAL,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093',\
    chain"
    SecRule &REQUEST_HEADERS:Authorization "@eq 0" \
        "t:none"

# Block unauthenticated access to Redfish API endpoints
SecRule REQUEST_URI "@beginsWith /redfish/v1" \
    "id:202620093002,\
    phase:1,\
    block,\
    msg:'CVE-2026-20093: Potential authentication bypass attempt on Redfish API',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:CRITICAL,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093',\
    chain"
    SecRule &REQUEST_HEADERS:Authorization "@eq 0" \
        "t:none"

# Block unauthenticated access to XML API endpoints
SecRule REQUEST_URI "@beginsWith /xmlapi" \
    "id:202620093003,\
    phase:1,\
    block,\
    msg:'CVE-2026-20093: Potential authentication bypass attempt on XML API',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:CRITICAL,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093',\
    chain"
    SecRule &REQUEST_HEADERS:Authorization "@eq 0" \
        "t:none"

# Detect malformed or suspicious authentication headers
SecRule REQUEST_HEADERS:Authorization "@detectSQLi" \
    "id:202620093004,\
    phase:1,\
    block,\
    msg:'CVE-2026-20093: Suspicious authorization header detected',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:WARNING,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093'"

# Block attempts to bypass authentication with empty or null values
SecRule REQUEST_HEADERS:Authorization "@rx ^(null|undefined|\\s*|\"\"|\'\')$" \
    "id:202620093005,\
    phase:1,\
    block,\
    msg:'CVE-2026-20093: Authentication bypass attempt with null/empty authorization',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:CRITICAL,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093'"

# Block suspicious user-agent strings targeting IMC
SecRule REQUEST_HEADERS:User-Agent "@rx (?i)(curl|wget|python|perl|ruby|powershell|exploit|scanner)" \
    "id:202620093006,\
    phase:1,\
    deny,\
    status:403,\
    msg:'CVE-2026-20093: Suspicious user-agent accessing IMC endpoints',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:WARNING,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093',\
    chain"
    SecRule REQUEST_URI "@rx ^/(imc|redfish|xmlapi)" \
        "t:none"

# Block attempts to access admin functions without proper authentication
SecRule REQUEST_URI "@rx (?i)/(imc|redfish/v1|xmlapi).*(admin|config|settings|users|accounts|privileges)" \
    "id:202620093007,\
    phase:1,\
    block,\
    msg:'CVE-2026-20093: Attempt to access administrative functions',\
    logdata:'Matched Data: %{MATCHED_VAR} found within %{MATCHED_VAR_NAME}',\
    severity:CRITICAL,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093',\
    chain"
    SecRule &REQUEST_HEADERS:Authorization "@eq 0" \
        "t:none"

# Rate limiting for authentication attempts
SecRule REQUEST_URI "@rx ^/(imc|redfish/v1|xmlapi)" \
    "id:202620093008,\
    phase:1,\
    pass,\
    nolog,\
    setvar:'ip.auth_attempts=+1',\
    expirevar:'ip.auth_attempts=300',\
    tag:'cve-2026-20093'"

SecRule IP:AUTH_ATTEMPTS "@gt 10" \
    "id:202620093009,\
    phase:1,\
    deny,\
    status:429,\
    msg:'CVE-2026-20093: Rate limit exceeded for authentication attempts',\
    logdata:'IP: %{REMOTE_ADDR} - Attempts: %{ip.auth_attempts}',\
    severity:WARNING,\
    tag:'attack-auth-bypass',\
    tag:'cve-2026-20093',\
    setvar:'ip.blocked=1',\
    expirevar:'ip.blocked=3600'"

# mod_rewrite rules for additional protection
RewriteEngine On

# Redirect unauthenticated requests to login page
RewriteCond %{REQUEST_URI} ^/(imc|redfish/v1|xmlapi)
RewriteCond %{HTTP:Authorization} ^$
RewriteRule ^(.*)$ - [F,L]

# Block direct access to sensitive files
RewriteRule ^/(imc|redfish|xmlapi).*\.(conf|config|xml|json|log)$ - [F,L]

# Enforce HTTPS for all IMC endpoints
RewriteCond %{HTTPS} off
RewriteCond %{REQUEST_URI} ^/(imc|redfish/v1|xmlapi)
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

:material-file-download: prevention/httpd.conf

Frequently asked questions

What is CVE-2026-20093?

CVE-2026-20093 is a Critical (9.8) vulnerability: This repository contains a proof-of-concept (PoC) exploit for CVE-2026-20093, a critical…. This entry ships ready-to-deploy detection and prevention rules (Snort, YARA, Nginx, Apache) plus a detection-only PoC and a Docker test lab.

How do I detect CVE-2026-20093?

Deploy the Snort and YARA detection rule included with this entry (see Detection & prevention rules below), then validate it against the detection-only PoC in the Docker test lab.

How do I block or mitigate CVE-2026-20093?

Apply the Nginx and Apache mitigation config included with this entry, and upgrade to a fixed version per the vendor advisory (see the NVD record for affected versions).

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For authorized security testing and research only. See the full source and NVD record.