PHP FastCGI Process Manager (FPM) Buffer Overflow Vulnerability
In some versions of PHP in certain configurations of FPM setup, it is possible to cause FPM module to write past allocated buffers allowing the possibility of remote code execution.
A remote attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2022-04-15 under CISA BOD 22-01.
This is a Classic Buffer Overflow (CWE-120) vulnerability in PHP FastCGI Process Manager (FPM). In PHP versions 7.1.x below 7.1.33, 7.2.x below 7.2.24 and 7.3.x below 7.3.11 in certain configurations of FPM setup it is possible to cause FPM module to write past allocated buffers into the space reserved for FCGI protocol data, thus opening the possibility of remote code execution. Exploitation requires remote network access, higher attack complexity, no authentication required, and no user interaction required.
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Phishing link
🖼
Malicious file
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Server compromised
Probably yes if any of these apply:
Used in known ransomware campaigns. Threat-research write-up: http://packetstormsecurity.com/files/156642/PHP-FPM-7.x-Remote-Code-Execution.html
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply updates per vendor instructions.
References
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References