CVE-2026-45133
published 2026-07-14CVE-2026-45133: 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…
PriorityP344high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.74%
50.9th percentile
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
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| sensiolabs | symfony | < 5.4.52 | 5.4.52 |
| sensiolabs | symfony | >= 6.0.0 < 6.4.40 | 6.4.40 |
| sensiolabs | symfony | >= 7.0.0 < 7.4.12 | 7.4.12 |
| sensiolabs | symfony | >= 8.0.0 < 8.0.12 | 8.0.12 |
| symfony | symfony | < 5.4.52 | 5.4.52 |
| symfony | symfony | — | — |
| symfony | symfony | — | — |
| symfony | symfony | — | — |
| symfony | symfony | >= 0 < 5.4.52 | 5.4.52 |
| symfony | symfony | >= 6.0.0 < 6.4.40 | 6.4.40 |
| symfony | symfony | >= 7.0.0 < 7.4.12 | 7.4.12 |
| symfony | symfony | >= 8.0.0 < 8.0.12 | 8.0.12 |
| symfony | yaml | >= 0 < 5.4.52 | 5.4.52 |
| symfony | yaml | >= 6.0.0 < 6.4.40 | 6.4.40 |
| symfony | yaml | >= 7.0.0 < 7.4.12 | 7.4.12 |
| symfony | yaml | >= 8.0.0 < 8.0.12 | 8.0.12 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.2HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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VulDB
Symfony recursion
vuldb·2026-05-28
CVE-2026-45133 [LOW] Symfony recursion
A vulnerability was found in Symfony and classified as problematic. This affects an unknown function. Such manipulation leads to uncontrolled recursion.
This vulnerability is uniquely identified as CVE-2026-45133. The attack can be launched remotely. No exploit exists.
It is suggested to upgrade the affected component.
GHSA
Symfony hardened the parser when handling untrusted input
ghsa·2026-05-27
CVE-2026-45133 [LOW] CWE-1333 Symfony hardened the parser when handling untrusted input
Symfony hardened the parser when handling untrusted input
### 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::parseF
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-14
Published