CVE-2026-45186

libexpat: denial of service via crafted XML input

Published May 10, 2026 CVSS 3.1 · 2.9 Low EPSS < 1% KEV · Not listed
Description
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4807-1 expat security update
Debian DSA Debian DSA DSA-6404-1 expat security update
Ubuntu USN Ubuntu USN USN-8790-1 Expat vulnerabilities
History
Type Values Removed Values Added
Title Denial of Service via Attribute Name Collision in libexpat libexpat: denial of service via crafted XML input
References
Metrics threat_severity

None

threat_severity

Important

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Denial of Service via Attribute Name Collision in libexpat
Type Values Removed Values Added
Description In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
First Time appeared Libexpat Project
Libexpat Project libexpat
Weaknesses CWE-407
CPEs cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*
Vendors & Products Libexpat Project
Libexpat Project libexpat
References
Metrics cvssV3_1

{'score': 2.9, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Nov 10, 2026, 12:46 PM
Reserved
May 10, 2026, 6:36 AM
Status
Modified
Published
May 10, 2026, 7:16 AM
Modified
Nov 10, 2026, 1:19 PM
Severity
Important
Public date
May 10, 2026, 6:36 AM