Inefficient Algorithmic Complexity Affecting expat package, versions [,2.8.4)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-CONAN-EXPAT-21707507
- published25 Oct 2026
- disclosed18 Aug 2026
- creditUnknown
Introduced: 18 Aug 2026
CVE-2026-66046 (opens in a new tab)How to fix?
Upgrade expat to version 2.8.4 or higher.
Overview
Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity in the storeAtts function. An attacker can cause excessive CPU consumption by supplying a specially crafted XML document with numerous attributes containing non-normalized values, leading to significant resource exhaustion during parsing.