---
title: "CVE-2026-109618: RCE via OOM corruption"
url: https://erroneo.us/security/cve/CVE-2026-109618/
description: "CVE-2026-109618 (PHP Group PHP): PHP uses longjmp() for out-of-memory (OOM) errors to exit the current context and abort handling of the request. Some…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-21
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-109618"
kev: false
cvss: 9.2
epss: null
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-109618: RCE via OOM corruption

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Editorial verdict: Act now. PHP2Shell: Critical Unauthenticated RCE in PHP — If PHP answers HTTP requests anywhere you run it, patch or apply a vendor fix today; this is pre-application, unauthenticated, and attack traffic started before the patch shipped.

## 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).

## Affected products (CVE record)

- PHP Group PHP: 8.2.* < 8.2.35, 8.3.* < 8.3.36, 8.4.* < 8.4.27, 8.5.* < 8.5.12

## Severity

- php CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact total .

## Sources

- [github.com](https://github.com/php/php-src/security/advisories/GHSA-w8hw-w9fx-j79w)
- [CVE.org record CVE-2026-109618](https://www.cve.org/CVERecord?id=CVE-2026-109618)
- [NVD entry CVE-2026-109618](https://nvd.nist.gov/vuln/detail/CVE-2026-109618)
- [wiz.io](https://www.wiz.io/blog/php2shell-php-rce)
- [openwall.com](http://www.openwall.com/lists/oss-security/2026/10/21/6)

---
Source page: https://erroneo.us/security/cve/CVE-2026-109618/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt