USN-8520-1: Expat vulnerability

unknownCVE-2026-41080

It was discovered that Expat used insufficient entropy when generating hash salt values for its internal hash table. An attacker could use this to craft an XML document that triggers hash flooding, leading to a denial of service.

CSIRTS triage

vendor: Expat product: Expat Denial of service

What: Expat uses insufficient entropy for hash salt values, which can lead to denial of service through hash flooding.
Who is affected: Deployments of Expat that process XML documents are affected.
Urgency: Remediation is urgent due to the potential for denial of service attacks.
Action: Update to the latest version of Expat to resolve this issue.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Ubuntu Security Notices (INTL · vendor-psirt · site)
Severity: unknown
Published: 2026-07-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://ubuntu.com/security/notices/USN-8520-1

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-410800.38% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 30% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-41080	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

low[UPDATE] [low] expat: Vulnerability allows Denial of Servicecert-bund