Improper Handling of Unicode Encoding Affecting expat package, versions <0:2.5.0-4.el8_10


Severity

Recommended
0.0
high
0
10

Based on AlmaLinux security rating.

Threat Intelligence

EPSS
0.4% (33rd percentile)

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  • Snyk IDSNYK-ALMALINUX8-EXPAT-20250201
  • published29 Sept 2026
  • disclosed28 Sept 2026

Introduced: 28 Sep 2026

NewCVE-2026-93990  (opens in a new tab)
CWE-176  (opens in a new tab)

How to fix?

Upgrade AlmaLinux:8 expat to version 0:2.5.0-4.el8_10 or higher.
This issue was patched in ALSA-2026:72448.

NVD Description

Note: Versions mentioned in the description apply only to the upstream expat package and not the expat package as distributed by AlmaLinux. See How to fix? for AlmaLinux:8 relevant fixed versions and status.

Expat before 2.8.5 fails to validate that a high surrogate in UTF-16 input is followed by a low surrogate, allowing malformed UTF-16 sequences to be accepted. Attackers can supply UTF-16 encoded XML containing lone high surrogates that consume the following code unit, causing Expat to pass unpaired surrogates to applications built with XML_UNICODE and to silently replace input characters in other builds.

CVSS Base Scores

version 3.1