CVE-2026-45186: CWE-407 Inefficient Algorithmic Complexity in libexpat project libexpat
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.
AI Analysis
Technical Summary
The libexpat library prior to version 2.8.1 contains an inefficient algorithmic complexity issue (CWE-407) in the handling of attribute name collision checks. This flaw allows an attacker to craft XML input that triggers excessive computational effort, leading to a denial of service condition. The vulnerability requires local access and has a high attack complexity, with no impact on confidentiality or integrity, only availability.
Potential Impact
The impact is limited to denial of service caused by resource exhaustion during XML parsing. There is no confidentiality or integrity impact. Exploitation requires local access and a high level of effort due to the complexity of the attack. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or remediation level is provided, users should monitor libexpat project communications for updates. Until a fix is available, avoid processing untrusted XML input locally or implement resource limits on XML parsing where possible.
CVE-2026-45186: CWE-407 Inefficient Algorithmic Complexity in libexpat project libexpat
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.
CVSS v3.1
Score 2.9low
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The libexpat library prior to version 2.8.1 contains an inefficient algorithmic complexity issue (CWE-407) in the handling of attribute name collision checks. This flaw allows an attacker to craft XML input that triggers excessive computational effort, leading to a denial of service condition. The vulnerability requires local access and has a high attack complexity, with no impact on confidentiality or integrity, only availability.
Potential Impact
The impact is limited to denial of service caused by resource exhaustion during XML parsing. There is no confidentiality or integrity impact. Exploitation requires local access and a high level of effort due to the complexity of the attack. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or remediation level is provided, users should monitor libexpat project communications for updates. Until a fix is available, avoid processing untrusted XML input locally or implement resource limits on XML parsing where possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-05-10T06:36:15.697Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a002aeccbff5d86105df0a5
Added to database: 5/10/2026, 6:51:24 AM
Last enriched: 5/17/2026, 10:32:43 AM
Last updated: 6/17/2026, 10:52:02 PM
Views: 102
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