Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion') 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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Test your applications- Snyk IDSNYK-DEBIANUNSTABLE-SYMFONY-16896436
- published27 May 2026
- disclosed14 Jul 2026
Introduced: 27 May 2026
CVE-2026-45304 (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, Symfony\Component\Yaml\Parser resolved YAML collection aliases recursively, allowing a small untrusted YAML input to expand into a multi-gigabyte structure and exhaust memory. 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-2026-45304
- https://github.com/symfony/symfony/commit/e77391b2e4f18821198f010d573674c8ed4a970a
- 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-4qpc-3hr4-r2p4