CVE-2026-45304

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 resolved YAML collection aliases recursively, allowing a small untrusted YAML input to expand into a multi-gigabyte structure and exhaust memory. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/symfony/symfony/commit/e77391b2e4f18821198f010d573674c8ed4a970a	Patch
https://github.com/symfony/symfony/releases/tag/v5.4.52	Product Release Notes
https://github.com/symfony/symfony/releases/tag/v6.4.40	Product Release Notes
https://github.com/symfony/symfony/releases/tag/v7.4.12	Product Release Notes
https://github.com/symfony/symfony/releases/tag/v8.0.12	Product Release Notes
https://github.com/symfony/symfony/security/advisories/GHSA-4qpc-3hr4-r2p4	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:sensiolabs:symfony::::::::
	cpe:2.3:a:sensiolabs:symfony::::::::
	cpe:2.3:a:sensiolabs:symfony::::::::
	cpe:2.3:a:sensiolabs:symfony::::::::

History

No history.

Information

Published : 2026-07-14 19:17

Updated : 2026-07-15 14:55

NVD link : CVE-2026-45304

Mitre link : CVE-2026-45304

CVE.ORG link : CVE-2026-45304

JSON object : View

Products Affected

sensiolabs

symfony

CWE

CWE-776

Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')

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