Symfony: [Yaml] Harden the parser when handling untrusted input
Summary
| CVE | CVE-2026-45133 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-14 19:17:06 UTC |
| Updated | 2026-07-15 14:54:50 UTC |
| 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. |
Risk And Classification
Primary CVSS: v4.0 8.2 HIGH from [email protected]
CVSS: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
EPSS: 0.006020000 probability, percentile 0.447900000 (date 2026-07-15)
Problem Types: CWE-674 | CWE-776 | CWE-1333 | CWE-674 CWE-674: Uncontrolled Recursion | CWE-776 CWE-776: Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion') | CWE-1333 CWE-1333: Inefficient Regular Expression Complexity
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 8.2 | HIGH | CVSS: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/C... |
| 4.0 | CNA | DECLARED | 8.2 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| 3.1 | [email protected] | Primary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
CVSS: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
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Sensiolabs | Symfony | All | All | All | All |
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/symfony/symfony/releases/tag/v5.4.52 | [email protected] | github.com | Product, Release Notes |
| github.com/symfony/symfony/releases/tag/v6.4.40 | [email protected] | github.com | Product, Release Notes |
| github.com/symfony/symfony/releases/tag/v8.0.12 | [email protected] | github.com | Product, Release Notes |
| github.com/symfony/symfony/security/advisories/GHSA-c2p3-7m5p-cv8x | [email protected] | github.com | Patch, Vendor Advisory |
| github.com/symfony/symfony/releases/tag/v7.4.12 | [email protected] | github.com | Product, Release Notes |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |