Vulnerability in PHP Frankenphp
CVE-2026-122233
FrankenPHP before 1.13.4 contains an information disclosure vulnerability in worker mode that fails to clear last HTTP stream response headers between requests, because the reset only happens in RSHUTDOWN, which worker requests skip. Later requests calling http_get_last_response_headers() can read headers fetched by earlier requests on the same worker thread, exposing other users' Set-Cookie or token headers from backend APIs.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/php/frankenphp/commit/3fade63bb1c1d246926ed8a00520015f94cdc819 (patch)
- frankenphp v1.13.4 Release Notes (release-notes)
- GitHub Security Advisory (GHSA-pmvg-8483-mw84) (vendor-advisory)
- VulnCheck Advisory: FrankenPHP before 1.13.4 Cross-Request Response Header Leak in Worker Mode (third-party-advisory)
Frequently asked questions
- What is CVE-2026-122233?
- CVE-2026-122233 is a low-severity vulnerability in PHP Frankenphp, classified under CWE-488. CVSS score: 3.7/10. Published 2026-11-04.
- How severe is CVE-2026-122233?
- Low severity. CVSS v3 base score is 3.7 out of 10.