CVE-2026-102633

high

Description

libexpat versions 2.7.2 through 2.8.5 contain an integer overflow vulnerability in expat_realloc() function on 32-bit platforms when computing allocation sizes. Attackers supplying malicious XML to applications parsing with vulnerable libexpat can cause heap buffer overflow, memory corruption, or denial of service.

References

https://www.vulncheck.com/advisories/libexpat-2.7.2-through-2.8.5-integer-overflow-in-expat-realloc

https://github.com/libexpat/libexpat/pull/1392

https://github.com/libexpat/libexpat/commit/209801d7fbaf07ab74bae8cb32dd2ab9e5846118

https://github.com/libexpat/libexpat/blob/R_2_8_5/expat/lib/xmlparse.c#L1003

https://github.com/libexpat/libexpat

Details

Source: Mitre, NVD

Published: 2026-09-29

Updated: 2026-09-29

Risk Information

CVSS v2

Base Score: 5.4

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

Severity: Medium

CVSS v3

Base Score: 5.9

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

CVSS v4

Base Score: 8.2

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

Severity: High