Vulnerability 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, when the parser is exposed to attacker-controlled input, deeply nested mappings or sequences cause both the block-level (Parser::parseBlock()) and inline (Inline::parseSequence() / Inline::parseMapping()) parsers to recurse without a depth limit. A crafted document exhausts the PHP stack and crashes the worker. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Sensiolabs | Symfony | < 5.4.52 |
Related Weaknesses (CWE)
References
- https://github.com/symfony/symfony/releases/tag/v5.4.52ProductRelease Notes
- https://github.com/symfony/symfony/releases/tag/v6.4.40ProductRelease Notes
- https://github.com/symfony/symfony/releases/tag/v7.4.12ProductRelease Notes
- https://github.com/symfony/symfony/releases/tag/v8.0.12ProductRelease Notes
- https://github.com/symfony/symfony/security/advisories/GHSA-c2p3-7m5p-cv8xPatchVendor Advisory
FAQ
What is CVE-2026-45133?
CVE-2026-45133 is a vulnerability with a CVSS score of 7.5 (HIGH). 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, when the parser is exposed to attacker-controlled input, ...
How severe is CVE-2026-45133?
CVE-2026-45133 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-45133?
Check the references section above for vendor advisories and patch information. Affected products include: Sensiolabs Symfony.