Integer Overflow or Wraparound Affecting expat-static package, versions <0:2.1.0-15.amzn2.0.8


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.17% (7th percentile)

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  • Snyk IDSNYK-AMZN2-EXPATSTATIC-18059760
  • published21 Jul 2026
  • disclosed21 Jun 2026

Introduced: 21 Jun 2026

CVE-2026-56407  (opens in a new tab)
CWE-190  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2 expat-static to version 0:2.1.0-15.amzn2.0.8 or higher.
This issue was patched in ALAS2-2026-3800.

NVD Description

Note: Versions mentioned in the description apply only to the upstream expat-static package and not the expat-static package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2 relevant fixed versions and status.

libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.

CVSS Base Scores

version 3.1