CVE-2026-56409

Vendorlibexpat projectProductlibexpatDiscoveredJun 21, 2026UpdatedOct 25, 2026

xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.

CVSS v3.1

6.5 MEDIUM

EPSS

0.12%

probability of exploitation in 30 days

CISA KEV

Not listed

no confirmed exploitation reported

News coverage

sources referencing this CVE

Related IOCs

seen in the same coverage

Intelligence Reports1

1 intelligence report available

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EPSS Trend

Sep 17, 2026 → Sep 28, 2026

● 0.00pp

0.12% → 0.12% over 3 tracked changes

CVSS v3.1 Detail

Attack VectorLOCAL

Attack ComplexityHIGH

Privileges RequiredNONE

User InteractionREQUIRED

ScopeUNCHANGED

ConfidentialityHIGH

IntegrityHIGH

AvailabilityLOW

CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:L

Connections

3 relationships

Timeline

disclosure → media coverage

Jun 21, 2026

Disclosure — published as a CVE record. · last revised by NVD Oct 25, 2026

Sep 24, 2026

ubuntu.com reports: USN-8813-1: Expat vulnerabilities