Algorithmic Complexity Affecting expat-debugsource package, versions <0:2.7.3-1.el10_2.5


Severity

Recommended
0.0
high
0
10

Based on Rocky Linux security rating.

Threat Intelligence

EPSS
0.74% (53rd percentile)

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  • Snyk IDSNYK-ROCKY10-EXPATDEBUGSOURCE-20378333
  • published2 Oct 2026
  • disclosed18 Aug 2026

Introduced: 18 Aug 2026

CVE-2026-66046  (opens in a new tab)
CWE-407  (opens in a new tab)

How to fix?

Upgrade Rocky-Linux:10 expat-debugsource to version 0:2.7.3-1.el10_2.5 or higher.
This issue was patched in RLSA-2026:74001.

NVD Description

Note: Versions mentioned in the description apply only to the upstream expat-debugsource package and not the expat-debugsource package as distributed by Rocky-Linux. See How to fix? for Rocky-Linux:10 relevant fixed versions and status.

Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType->defaultAtts to determine CDATA status. A remote unauthenticated attacker can supply a single well-formed XML document of a few megabytes to an application parsing untrusted XML to cause excessive CPU consumption, resulting in denial of service without requiring authentication, external entity resolution, or non-default parser options.

CVSS Base Scores

version 3.1