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.
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 | — |
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-c2p3-7m5p-cv8x |
| Packagist | symfony/symfony | >= 6.0.0, < 6.4.40 | 6.4.40 | GHSA-c2p3-7m5p-cv8x |
| Packagist | symfony/symfony | >= 7.0.0, < 7.4.12 | 7.4.12 | GHSA-c2p3-7m5p-cv8x |
| Packagist | symfony/symfony | >= 8.0.0, < 8.0.12 | 8.0.12 | GHSA-c2p3-7m5p-cv8x |
| Packagist | symfony/yaml | < 5.4.52 | 5.4.52 | GHSA-c2p3-7m5p-cv8x |
| Packagist | symfony/yaml | >= 6.0.0, < 6.4.40 | 6.4.40 | GHSA-c2p3-7m5p-cv8x |
| Packagist | symfony/yaml | >= 7.0.0, < 7.4.12 | 7.4.12 | GHSA-c2p3-7m5p-cv8x |
| Packagist | symfony/yaml | >= 8.0.0, < 8.0.12 | 8.0.12 | GHSA-c2p3-7m5p-cv8x |
Advisories 1
- WID-SEC-2026-1805 Zabbix: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 14, 2026