TeamSpeak 3 Server up to 3.13.7 Connection State Management process_resend_queue use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability was found in TeamSpeak 3 Server up to 3.13.7 and classified as critical. This vulnerability affects the function process_resend_queue of the component Connection State Management. Such manipulation leads to use after free. This vulnerability is traded as CVE-2026-4390. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in TeamSpeak 3 Server up to 3.13.7 and classified as critical. Affected by this issue is the function process_resend_queue of the component Connection State Management. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is integrity, and availability.

The weakness was shared by Michael Imfeld with modzero as MZ-26-01. The advisory is available at modzero.com. This vulnerability is handled as CVE-2026-4390. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit.

Upgrading to version 3.13.8 eliminates this vulnerability. The upgrade is hosted for download at teamspeak.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-32580). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • TeamSpeak 3 Server up to 3.13.7
  • TeamSpeak SDK Server-Side Integrations up to 3.3.1

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.5

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score: 7.1
Vendor Vector: 🔒

Researcher Base Score: 7.1
Researcher Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: TeamSpeak 3 Server 3.13.8

Timelineinfo

05/27/2026 Advisory disclosed
05/27/2026 +0 days VulDB entry created
05/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: MZ-26-01
Researcher: Michael Imfeld
Organization: modzero
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-4390 (🔒)
GCVE (CVE): GCVE-0-2026-4390
GCVE (VulDB): GCVE-100-366314
EUVD: 🔒

Entryinfo

Created: 05/27/2026 18:22
Updated: 05/27/2026 21:12
Changes: 05/27/2026 18:22 (54), 05/27/2026 18:26 (23), 05/27/2026 18:27 (1), 05/27/2026 21:12 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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