CVE-2026-45133
Symfony hardened the parser when handling untrusted input
描述
### Description `Symfony\Component\Yaml\Parser` is the entry point for parsing YAML strings into PHP values via `Yaml::parse()`. 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. ### Resolution The `Parser` now tracks recursion depth in a shared `ParserState` object across both block-level and inline parsing, with a default limit of **128**. The limit is configurable via a new `$maxNestingLevel` argument on `Parser::__construct()`, `Yaml::parse()` and `Yaml::parseFile()`. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/914f427ed9630ddb3904dafba763e53d9f133fe3) for branch 5.4. ### Credits Symfony would like to thank Pietro Tirenna (Shielder) for reporting the issue and Nicolas Grekas for fixing it.
受影響套件(3)
- Debian/symfonyfrom 0
- Packagist/symfony/symfonyfrom 0, < 5.4.52
- Packagist/symfony/yamlfrom 0, < 5.4.52
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U |
參考連結(7)
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2026-45133
- PATCHhttps://github.com/symfony/symfony
- WEBhttps://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-45133.yaml
- WEBhttps://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/yaml/CVE-2026-45133.yaml
- WEBhttps://github.com/symfony/symfony/commit/914f427ed9630ddb3904dafba763e53d9f133fe3
- WEBhttps://github.com/symfony/symfony/security/advisories/GHSA-c2p3-7m5p-cv8x
- WEBhttps://symfony.com/cve-2026-45133