# CVE-2026-45063: symfony: Symfony is a PHP framework for web and console applications and a set of reusable PHP components

CVE-2026-45063 is fixed in symfony on 1 platform, first by DEBIAN-CVE-2026-45063, released May 27, 2026. It is not reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2026-45063
- Priority: Urgent
- CVSS: 9.1 (critical)
- EPSS: 0.0034
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 14, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | symfony Debian 12.15 (bookworm) | 5.4.53+dfsg-0+deb12u1 | [DEBIAN-CVE-2026-45063](https://patchblox.com/security/data/fix/linux/debian-cve-2026-45063.md) | May 27, 2026 |
| Linux | symfony Debian 13.5 (trixie) | 6.4.41+dfsg-0+deb13u1 | [DEBIAN-CVE-2026-45063](https://patchblox.com/security/data/fix/linux/debian-cve-2026-45063.md) | May 27, 2026 |
| Linux | symfony Debian 14 | 7.4.12+dfsg-1 | [DEBIAN-CVE-2026-45063](https://patchblox.com/security/data/fix/linux/debian-cve-2026-45063.md) | May 27, 2026 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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