PT-2026-51239 · Libexpat · Libexpat

Hartwork · Published 2026-06-21 · Updated 2026-06-21 · CVE-2026-56403

Positive Technologies (AI Summary)

CVSS v3.1

6.9

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions libexpat versions prior to 2.8.2

Description An integer overflow exists in the storeAtts() function. An integer overflow occurs when an arithmetic operation attempts to create a numeric value that is outside of the range that can be represented with a given number of bits.

Recommendations Update to version 2.8.2 or later. As a temporary workaround, restrict the use of the storeAtts() function until the update is applied.

Fix

Integer Overflow

Weakness Enumeration

CWE-190

Related Identifiers

CVE-2026-56403

Affected Products

Libexpat

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-56403 · Security Note
• https://github.com/libexpat/libexpat/pull/1232 · Note
• https://twitter.com/CVEnew/status/2068747028683702547 · Twitter Post