CVE-2026-45304

EUVD-2026-44358
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.
XML Entity Expansion
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 49.83%
Affected Products (NVD)
VendorProductVersion
sensiolabssymfony
𝑥
< 5.4.52
sensiolabssymfony
6.0.0 ≤
𝑥
< 6.4.40
sensiolabssymfony
7.0.0 ≤
𝑥
< 7.4.12
sensiolabssymfony
8.0.0 ≤
𝑥
< 8.0.12
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
symfony
bookworm
5.4.53+dfsg-0+deb12u1
fixed
bookworm (security)
5.4.53+dfsg-0+deb12u1
fixed
bullseye
vulnerable
bullseye (security)
vulnerable
forky
7.4.16+dfsg-1
fixed
sid
7.4.17+dfsg-1
fixed
trixie
6.4.41+dfsg-0+deb13u1
fixed
trixie (security)
6.4.41+dfsg-0+deb13u1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
symfony
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
ignored
resolute
needs-triage
xenial
needs-triage
Common Weakness Enumeration
References
https://github.com/symfony/symfony/commit/e77391b2e4f18821198f010d573674c8ed4a970a
https://github.com/symfony/symfony/releases/tag/v5.4.52
https://github.com/symfony/symfony/releases/tag/v6.4.40
https://github.com/symfony/symfony/releases/tag/v7.4.12
https://github.com/symfony/symfony/releases/tag/v8.0.12
https://github.com/symfony/symfony/security/advisories/GHSA-4qpc-3hr4-r2p4