cgi_main.c in PHP before 5.3.12 and 5.4.x before 5.4.2, when configured as a CGI…¶

Key facts

CVE-2012-1823 is a Critical (9.8) vulnerability: sapi/cgi/cgi_main.c in PHP before 5.3.12 and 5.4.x before 5.4.2, when configured as a CGI…. This entry ships a detection-only PoC and a Docker test lab. It is on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2022-03-25), confirming active exploitation in the wild.

Actively exploited — on the CISA KEV catalog

CVE-2012-1823 is listed on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2022-03-25), confirming exploitation in the wild. Federal remediation deadline: 2022-04-15. Prioritise patching and deploy the detection and prevention rules below.


CVE	CVE-2012-1823
Severity	Critical (9.8)
CISA KEV	Actively exploited (added 2022-03-25)
Detection / prevention	—
PoC	poc.py
Source	2012/CVE-2012-1823/

Details¶

English | 한국어

Description¶

sapi/cgi/cgi_main.c in PHP before 5.3.12 and 5.4.x before 5.4.2, when configured as a CGI script (aka php-cgi), does not properly handle query strings that lack an = (equals sign) character, which allows remote attackers to execute arbitrary code by placing command-line options in the query string, related to lack of skipping a certain php_getopt for the 'd' case.

Vulnerability Details¶

Property	Value
CVE ID	CVE-2012-1823
Type	COMMAND_INJECTION
CVSS Score	9.8

Proof of Concept¶

Download¶

# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2012/CVE-2012-1823/poc.py

Usage¶

# Run PoC against target
python3 poc.py --target <TARGET_URL>

# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>

⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.

Test Lab¶

This repository includes a Docker-based test environment with both vulnerable and patched applications.

Quick Start¶

# Clone and navigate to CVE directory
cd CVE-2012-1823

# Start both applications
docker-compose up -d

# Run tests
./run-tests.sh    # Linux/Mac
./run-tests.ps1   # Windows PowerShell

Application Endpoints¶

Application	URL	Status
Vulnerable App	http://localhost:8080	Shows vulnerability
Patched App	http://localhost:8081	Demonstrates fix

Directory Structure¶

├── README.md           # English documentation
├── README_KO.md        # Korean documentation
├── poc.py              # PoC detection script
├── docker-compose.yml  # Container orchestration
├── run-tests.sh        # Linux/Mac test runner
├── run-tests.ps1       # Windows test runner
├── vulnerable-app/     # Vulnerable version
│   ├── app.py
│   ├── Dockerfile
│   └── requirements.txt
└── patched-app/        # Fixed version
    ├── app.py
    ├── Dockerfile
    └── requirements.txt

References¶

http://eindbazen.net/2012/05/php-cgi-advisory-cve-2012-1823/
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03360041
http://lists.apple.com/archives/security-announce/2012/Sep/msg00004.html
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00007.html
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00011.html
http://marc.info/?l=bugtraq&m=134012830914727&w=2
http://rhn.redhat.com/errata/RHSA-2012-0546.html
http://rhn.redhat.com/errata/RHSA-2012-0547.html
http://rhn.redhat.com/errata/RHSA-2012-0568.html
http://rhn.redhat.com/errata/RHSA-2012-0569.html
http://rhn.redhat.com/errata/RHSA-2012-0570.html
http://secunia.com/advisories/49014
http://secunia.com/advisories/49065
http://secunia.com/advisories/49085
http://secunia.com/advisories/49087
http://support.apple.com/kb/HT5501
http://www.debian.org/security/2012/dsa-2465
http://www.kb.cert.org/vuls/id/520827
http://www.kb.cert.org/vuls/id/673343
http://www.mandriva.com/security/advisories?name=MDVSA-2012:068
http://www.openwall.com/lists/oss-security/2024/06/07/1
http://www.php.net/ChangeLog-5.php#5.4.2
http://www.php.net/archive/2012.php#id2012-05-03-1
http://www.securitytracker.com/id?1027022
https://bugs.php.net/bug.php?id=61910
https://bugs.php.net/patch-display.php?bug_id=61910&patch=cgi.diff&revision=1335984315&display=1
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PKGTQUOA2NTZ3RXN22CSAUJPIRUYRB4B/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W45DBOH56NQDRTOM2DN2LNA2FZIMC3PK/
http://eindbazen.net/2012/05/php-cgi-advisory-cve-2012-1823/
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03360041
http://lists.apple.com/archives/security-announce/2012/Sep/msg00004.html
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00007.html
http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00011.html
http://marc.info/?l=bugtraq&m=134012830914727&w=2
http://rhn.redhat.com/errata/RHSA-2012-0546.html
http://rhn.redhat.com/errata/RHSA-2012-0547.html
http://rhn.redhat.com/errata/RHSA-2012-0568.html
http://rhn.redhat.com/errata/RHSA-2012-0569.html
http://rhn.redhat.com/errata/RHSA-2012-0570.html
http://secunia.com/advisories/49014
http://secunia.com/advisories/49065
http://secunia.com/advisories/49085
http://secunia.com/advisories/49087
http://support.apple.com/kb/HT5501
http://www.debian.org/security/2012/dsa-2465
http://www.kb.cert.org/vuls/id/520827
http://www.kb.cert.org/vuls/id/673343
http://www.mandriva.com/security/advisories?name=MDVSA-2012:068
http://www.openwall.com/lists/oss-security/2024/06/07/1
http://www.php.net/ChangeLog-5.php#5.4.2
http://www.php.net/archive/2012.php#id2012-05-03-1
http://www.securitytracker.com/id?1027022
https://bugs.php.net/bug.php?id=61910
https://bugs.php.net/patch-display.php?bug_id=61910&patch=cgi.diff&revision=1335984315&display=1
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PKGTQUOA2NTZ3RXN22CSAUJPIRUYRB4B/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W45DBOH56NQDRTOM2DN2LNA2FZIMC3PK/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PKGTQUOA2NTZ3RXN22CSAUJPIRUYRB4B/
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2012-1823

Generated by PoC Generator on 2026-07-05T07:31:31.298308926

Frequently asked questions¶

What is CVE-2012-1823?¶

CVE-2012-1823 is a Critical (9.8) vulnerability: sapi/cgi/cgi_main.c in PHP before 5.3.12 and 5.4.x before 5.4.2, when configured as a CGI…. This entry ships a detection-only PoC and a Docker test lab. It is on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2022-03-25), confirming active exploitation in the wild.

How do I detect CVE-2012-1823?¶

Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.

How do I block or mitigate CVE-2012-1823?¶

Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.

Is CVE-2012-1823 actively exploited?¶

Yes. CVE-2012-1823 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, added 2022-03-25, which means it has been exploited in the wild. CISA set a federal remediation deadline of 2022-04-15. Prioritise patching and deploy the detection and prevention rules above.

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