Deserialization of Untrusted Data Affecting symfony package, versions <7.4.12+dfsg-1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published27 May 2026
- disclosed14 Jul 2026
Introduced: 27 May 2026
CVE-2026-45077 (opens in a new tab)How to fix?
Upgrade Debian:unstable symfony to version 7.4.12+dfsg-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream symfony package and not the symfony package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
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, the server:log listener (Symfony\Bridge\Monolog\Command\ServerLogCommand) binds to 0.0.0.0:9911 by default and processes each received frame with unserialize(base64_decode($message)) without authentication, integrity checks, or an allowed_classes allowlist, allowing any reachable host to submit attacker-chosen serialized PHP payloads that can crash the listener and may trigger object-injection gadget effects. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.
References
- https://security-tracker.debian.org/tracker/CVE-2026-45077
- https://github.com/symfony/symfony/commit/0891b2f293896c488e26943dc034334364b77fc4
- https://github.com/symfony/symfony/releases/tag/v5.4.52
- https://github.com/symfony/symfony/releases/tag/v6.4.40
- https://github.com/symfony/symfony/releases/tag/v7.4.12
- https://github.com/symfony/symfony/releases/tag/v8.0.12
- https://github.com/symfony/symfony/security/advisories/GHSA-m7v2-7gxm-vc2v