CVE-2026-4392 (GCVE-0-2026-4392)

Vulnerability from cvelistv5 – Published: 2026-05-27 17:00 – Updated: 2026-05-28 15:04
VLAI
Title
TeamSpeak 3 Server clientek Handshake assertion
Summary
A vulnerability was detected in TeamSpeak 3 Server up to 3.13.7. This issue affects some unknown processing of the component clientek Handshake Handler. Performing a manipulation of the argument proof results in reachable assertion. Remote exploitation of the attack is possible. Upgrading to version 3.13.8 is capable of addressing this issue. Upgrading the affected component is recommended.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C
5.3 (Medium)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C
CWE
Assigner
References
Impacted products
Vendor Product Version
n/a TeamSpeak 3 Server Affected: 3.13.0
Affected: 3.13.1
Affected: 3.13.2
Affected: 3.13.3
Affected: 3.13.4
Affected: 3.13.5
Affected: 3.13.6
Affected: 3.13.7
Unaffected: 3.13.8
    cpe:2.3:a:teamspeak_3_server:teamspeak_3_server:*:*:*:*:*:*:*:*
Credits
Michael Imfeld (modzero)
Show details on NVD website
To clipboard 

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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.