Vulnerability in Sensiolabs Symfony
CVE-2026-45063
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.52, 6.4.40, 7.4.12, and 8.0.12, X509Authenticator extracts the user identifier from $_SERVER['SSL_CLIENT_S_DN'] with an unanchored regex that matches emailAddress= anywhere in the distinguished name, allowing an attacker with a trusted certificate containing emailAddress=victim inside another RDN value such as CN to authenticate as the victim. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (28.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 28.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Sensiolabs Symfony
- Symfony — versions < 5.4.52, >= 6.0.0-BETA1, < 6.4.40, >= 7.0.0-BETA1, < 7.4.12
Weakness classification (CWE)
References
- github.com/symfony/symfony/security/advisories/GHSA-ph86-p8f6-f9r2 (Patch, Vendor Advisory)
- github.com/symfony/symfony/commit/59ef484029601a7af06f5e06c6ed921fdcea5a0d (Patch)
- github.com/symfony/symfony/releases/tag/v5.4.52 (Product, Release Notes)
- github.com/symfony/symfony/releases/tag/v6.4.40 (Product, Release Notes)
- github.com/symfony/symfony/releases/tag/v7.4.12 (Product, Release Notes)
- github.com/symfony/symfony/releases/tag/v8.0.12 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-45063?
- CVE-2026-45063 is a critical-severity vulnerability in Sensiolabs Symfony, classified under Authentication Bypass by Spoofing. CVSS score: 9.1/10. Published 2026-07-14.
- How severe is CVE-2026-45063?
- Critical severity. CVSS v3 base score is 9.1 out of 10.