Known exploited · PHP
CVE-2012-1823: PHP-CGI Query String Parameter Vulnerability
What it is
sapi/cgi/cgi_main.c in PHP, when configured as a CGI script, does not properly handle query strings, which allows remote attackers to execute arbitrary code.
- Vendor
- PHP
- Product
- PHP
- Added to KEV
- March 25, 2022
- CISA due date
- April 15, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of PHP you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before April 15, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
Not sure you are clear?
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.