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, 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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| 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 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | symfony | 7.4.12+dfsg-1 | — |
| Debian 13 | symfony | 6.4.41+dfsg-0+deb13u1 | — |
| Debian 12 | symfony | 5.4.53+dfsg-0+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | symfony | No fix yet | — |
| Ubuntu 26.04 LTS | symfony | No fix yet | — |
| Ubuntu 25.10 | symfony | No fix yet | — |
| Ubuntu 16.04 LTS | symfony | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | symfony | No fix yet | — |
| Ubuntu Pro 22.04 LTS | symfony | No fix yet | — |
| Ubuntu Pro 20.04 LTS | symfony | No fix yet | — |
| Ubuntu Pro 18.04 LTS | symfony | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Packagist | symfony/symfony | < 5.4.52 | 5.4.52 | GHSA-9frc-8383-795m |
| Packagist | symfony/symfony | >= 6.0.0, < 6.4.40 | 6.4.40 | GHSA-9frc-8383-795m |
| Packagist | symfony/symfony | >= 7.0.0, < 7.4.12 | 7.4.12 | GHSA-9frc-8383-795m |
| Packagist | symfony/symfony | >= 8.0.0, < 8.0.12 | 8.0.12 | GHSA-9frc-8383-795m |
| Packagist | symfony/yaml | < 5.4.52 | 5.4.52 | GHSA-9frc-8383-795m |
| Packagist | symfony/yaml | >= 6.0.0, < 6.4.40 | 6.4.40 | GHSA-9frc-8383-795m |
| Packagist | symfony/yaml | >= 7.0.0, < 7.4.12 | 7.4.12 | GHSA-9frc-8383-795m |
| Packagist | symfony/yaml | >= 8.0.0, < 8.0.12 | 8.0.12 | GHSA-9frc-8383-795m |
Advisories 1
- WID-SEC-2026-1805 Zabbix: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 14, 2026
References
- https://github.com/symfony/symfony/security/advisories/GHSA-9frc-8383-795m
- https://github.com/symfony/symfony/commit/9749cd43c5e09b3735093623670b21b9d8a056cb
- 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