CVE-2026-56132

EUVD-2026-37977
In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
mitreCNA
6.9 MEDIUM
LOCAL
HIGH
NONE
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
libexpat_projectlibexpat
𝑥
< 2.8.2
CNA
Debian logo
Debian Releases
Debian Product
Codename
expat
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
vulnerable
forky
vulnerable
sid
vulnerable
trixie
vulnerable
Common Weakness Enumeration
Vulnerability Media Exposure
References
https://github.com/libexpat/libexpat/pull/1272