CVE-2026-4392: Reachable Assertion in TeamSpeak 3 Server
CVE-2026-4392 is a medium-severity vulnerability in TeamSpeak 3 Server versions up to 3.13.7. It involves a reachable assertion triggered by manipulation of the 'proof' argument in the clientek Handshake Handler component. This vulnerability can be exploited remotely. Upgrading to version 3.13.8 addresses the issue.
AI Analysis
Technical Summary
This vulnerability affects TeamSpeak 3 Server up to version 3.13.7 and is caused by improper handling of the 'proof' argument in the clientek Handshake Handler component, leading to a reachable assertion. The flaw allows remote attackers to trigger an assertion failure, potentially causing denial of service or other impacts. The CVSS 4.0 base score is 6.9, indicating medium severity, with attack vector network, no privileges or user interaction required, and low impact on availability. The vendor has released version 3.13.8 which mitigates this vulnerability.
Potential Impact
The vulnerability allows remote attackers to cause a reachable assertion in the TeamSpeak 3 Server, which may lead to denial of service or instability of the server. There is no indication of privilege escalation, information disclosure, or code execution from the provided data.
Mitigation Recommendations
Upgrade TeamSpeak 3 Server to version 3.13.8 or later, as this version addresses the vulnerability. No other mitigation or temporary fix is indicated. Patch status is confirmed by the recommendation to upgrade.
CVE-2026-4392: Reachable Assertion in TeamSpeak 3 Server
Description
CVE-2026-4392 is a medium-severity vulnerability in TeamSpeak 3 Server versions up to 3.13.7. It involves a reachable assertion triggered by manipulation of the 'proof' argument in the clientek Handshake Handler component. This vulnerability can be exploited remotely. Upgrading to version 3.13.8 addresses the issue.
CVSS v4.0
Score 6.9medium
Affected software
pkg:github/teamspeak/TeamSpeak-3-ServerRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability affects TeamSpeak 3 Server up to version 3.13.7 and is caused by improper handling of the 'proof' argument in the clientek Handshake Handler component, leading to a reachable assertion. The flaw allows remote attackers to trigger an assertion failure, potentially causing denial of service or other impacts. The CVSS 4.0 base score is 6.9, indicating medium severity, with attack vector network, no privileges or user interaction required, and low impact on availability. The vendor has released version 3.13.8 which mitigates this vulnerability.
Potential Impact
The vulnerability allows remote attackers to cause a reachable assertion in the TeamSpeak 3 Server, which may lead to denial of service or instability of the server. There is no indication of privilege escalation, information disclosure, or code execution from the provided data.
Mitigation Recommendations
Upgrade TeamSpeak 3 Server to version 3.13.8 or later, as this version addresses the vulnerability. No other mitigation or temporary fix is indicated. Patch status is confirmed by the recommendation to upgrade.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-03-18T15:06:05.814Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a172e7fe29bf47b50d78ac6
Added to database: 05/27/2026, 17:48:47 UTC
Last enriched: 06/03/2026, 20:50:17 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 102
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