CVE-2026-76956: CWE-394 Unexpected Status Code or Return Value in libexpat project libexpat
A vulnerability in libexpat versions 2.8.2 and 2.8.3 before 2.8.4 causes misinterpretation of the getentropy return code, leading to insufficient entropy. This weakness enables hash flooding attacks via crafted XML content, resulting in denial of service. The issue is tracked as CVE-2026-76956 with a high severity rating.
AI Analysis
Technical Summary
CVE-2026-76956 affects libexpat versions 2.8.2 and 2.8.3 prior to 2.8.4. The vulnerability arises from improper handling of the return value of the getentropy function, which leads to insufficient entropy generation. This insufficiency makes the library vulnerable to hash flooding attacks when processing crafted XML content, causing denial of service conditions. The CVSS v3.1 base score is 7.5, indicating a high severity with network attack vector, low attack complexity, no privileges or user interaction required, and impact limited to availability.
Potential Impact
Exploitation of this vulnerability can cause denial of service by triggering hash flooding attacks through crafted XML content. There is no impact on confidentiality or integrity reported. The attack can be performed remotely without authentication or user interaction.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is currently documented. Users should monitor libexpat project advisories for updates and apply patches once available.
CVE-2026-76956: CWE-394 Unexpected Status Code or Return Value in libexpat project libexpat
Description
A vulnerability in libexpat versions 2.8.2 and 2.8.3 before 2.8.4 causes misinterpretation of the getentropy return code, leading to insufficient entropy. This weakness enables hash flooding attacks via crafted XML content, resulting in denial of service. The issue is tracked as CVE-2026-76956 with a high severity rating.
CVSS v3.1
Score 7.5high
Affected software
pkg:github/libexpat/libexpatRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-76956 affects libexpat versions 2.8.2 and 2.8.3 prior to 2.8.4. The vulnerability arises from improper handling of the return value of the getentropy function, which leads to insufficient entropy generation. This insufficiency makes the library vulnerable to hash flooding attacks when processing crafted XML content, causing denial of service conditions. The CVSS v3.1 base score is 7.5, indicating a high severity with network attack vector, low attack complexity, no privileges or user interaction required, and impact limited to availability.
Potential Impact
Exploitation of this vulnerability can cause denial of service by triggering hash flooding attacks through crafted XML content. There is no impact on confidentiality or integrity reported. The attack can be performed remotely without authentication or user interaction.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is currently documented. Users should monitor libexpat project advisories for updates and apply patches once available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-08-20T04:22:50.503Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a86e0f3acd9273b4983850c
Added to database: 08/20/2026, 11:11:47 UTC
Last enriched: 08/20/2026, 11:22:17 UTC
Last updated: 08/20/2026, 14:08:51 UTC
Views: 4
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