CVE-2026-76921: CWE-416: Use After Free in Wireshark Foundation Wireshark
A use-after-free vulnerability exists in the CMS protocol dissector of Wireshark versions 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18. This flaw can cause the application to crash, resulting in a denial of service condition. The vulnerability has a medium severity rating with a CVSS score of 5.5.
AI Analysis
Technical Summary
CVE-2026-76921 is a use-after-free vulnerability (CWE-416) affecting the CMS protocol dissector in Wireshark versions 4.6.0 through 4.6.7 and 4.4.0 through 4.4.18. This vulnerability allows an attacker to cause a denial of service by triggering a crash in the affected dissector. The vulnerability requires local access with low complexity and user interaction. No confidentiality or integrity impact is indicated, only availability is affected.
Potential Impact
The vulnerability causes a denial of service by crashing Wireshark when processing specially crafted CMS protocol data. There is no impact on confidentiality or integrity. Exploitation requires user interaction and local access, limiting the attack vector.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are currently available. Users should monitor Wireshark Foundation advisories for updates and avoid processing untrusted CMS protocol data until a fix is released.
CVE-2026-76921: CWE-416: Use After Free in Wireshark Foundation Wireshark
Description
A use-after-free vulnerability exists in the CMS protocol dissector of Wireshark versions 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18. This flaw can cause the application to crash, resulting in a denial of service condition. The vulnerability has a medium severity rating with a CVSS score of 5.5.
CVSS v3.1
Score 5.5medium
Affected software
pkg:github/wireshark/wiresharkRun 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-2026-76921 is a use-after-free vulnerability (CWE-416) affecting the CMS protocol dissector in Wireshark versions 4.6.0 through 4.6.7 and 4.4.0 through 4.4.18. This vulnerability allows an attacker to cause a denial of service by triggering a crash in the affected dissector. The vulnerability requires local access with low complexity and user interaction. No confidentiality or integrity impact is indicated, only availability is affected.
Potential Impact
The vulnerability causes a denial of service by crashing Wireshark when processing specially crafted CMS protocol data. There is no impact on confidentiality or integrity. Exploitation requires user interaction and local access, limiting the attack vector.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are currently available. Users should monitor Wireshark Foundation advisories for updates and avoid processing untrusted CMS protocol data until a fix is released.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitLab
- Date Reserved
- 2026-08-19T22:44:30.531Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8633c7acd9273b49b8ad3a
Added to database: 08/19/2026, 22:52:55 UTC
Last enriched: 08/19/2026, 23:09:25 UTC
Last updated: 08/20/2026, 01:26:39 UTC
Views: 7
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