CVE-2026-45304

high

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, 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.

References

https://github.com/symfony/symfony/security/advisories/GHSA-4qpc-3hr4-r2p4

https://github.com/symfony/symfony/releases/tag/v8.0.12

https://github.com/symfony/symfony/releases/tag/v7.4.12

https://github.com/symfony/symfony/releases/tag/v6.4.40

https://github.com/symfony/symfony/releases/tag/v5.4.52

https://github.com/symfony/symfony/commit/e77391b2e4f18821198f010d573674c8ed4a970a

Details

Source: Mitre, NVD

Published: 2026-07-14

Updated: 2026-07-14

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 9.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

CVSS v4

Base Score: 8.7

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00076