PHP Group · PHP
CVE-2026-109618
RCE via OOM corruption
We wrote about this one: PHP2Shell: two critical flaws in PHP
What it is
PHP uses longjmp() for out-of-memory (OOM) errors to exit the current context and abort handling of the request. Some contexts may not properly account for this scenario and leave request memory in an uninitialized state before performing an allocation. The subsequent request cleanup procedure may read or branch on this memory. Multiple OOM strategies can consistently trigger this condition and lead to remote code execution (RCE).
CISA: PHP contains an out-of-memory corruption vulnerability that allows for unauthenticated remote code execution.
What to do
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Deadline for US federal agencies: October 29, 2026
More exploited flaws from PHP Group
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Oct 26, 2026 | Stale Internal Request-State | PHP | Critical 9.2 | >99.9% |
| Jun 12, 2024 | PHP-CGI OS Command Injection | PHP | Critical 9.8 | >99.9% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.