CVE-2026-45305
Symfony: YAML Parser ReDoS via Catastrophic Backtracking in Parser::cleanup() Regex
CVSS Score
0.0
EPSS Score
0.0%
EPSS Percentile
0th
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::cleanup() used regular expressions with overlapping quantifiers for YAML directive, comment, and document marker cleanup, allowing crafted input to make parsing hang for an arbitrarily long time. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.
| CWE | CWE-1333 |
| Vendor | symfony |
| Product | symfony |
| Published | Jul 14, 2026 |
| Last Updated | Jul 15, 2026 |
Stay Ahead of the Next One
Get instant alerts for symfony symfony
Be the first to know when new unknown vulnerabilities affecting symfony symfony are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
Affected Versions
symfony / symfony
< 5.4.52 >= 6.0.0-BETA1, < 6.4.40 >= 7.0.0-BETA1, < 7.4.12 >= 8.0.0-BETA1, < 8.0.12
symfony / yaml
< 5.4.52 >= 6.0.0-BETA1, < 6.4.40 >= 7.0.0-BETA1, < 7.4.12 >= 8.0.0-BETA1, < 8.0.12
References
github.com: https://github.com/symfony/symfony/security/advisories/GHSA-9frc-8383-795m github.com: https://github.com/symfony/symfony/commit/9749cd43c5e09b3735093623670b21b9d8a056cb github.com: https://github.com/symfony/symfony/releases/tag/v5.4.52 github.com: https://github.com/symfony/symfony/releases/tag/v6.4.40 github.com: https://github.com/symfony/symfony/releases/tag/v7.4.12 github.com: https://github.com/symfony/symfony/releases/tag/v8.0.12