CVE-2026-4390: Buffer Overflow (CVSS 5.4)

Description

A weakness has been identified in TeamSpeak 3 Server up to 3.13.7. This affects the function process_resend_queue of the component Connection State Management. This manipulation causes use after free. The attack may be initiated remotely. Upgrading to version 3.13.8 is able to mitigate this issue. The affected component should be upgraded.

Is your site exposed to CVE-2026-4390?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.16%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-119 Buffer Overflow

CWE-416 Use After Free

References

Other References

https://files.teamspeak-services.com/docs/security/TS-SA-2026-001.html https://modzero.com/en/advisories/mz-26-01-teamspeak/ https://vuldb.com/vuln/366314 https://vuldb.com/vuln/366314/cti https://www.teamspeak.com/en/downloads/#server

Frequently Asked Questions

What is CVE-2026-4390? +

A weakness has been identified in TeamSpeak 3 Server up to 3.13.7. This affects the function process_resend_queue of the component Connection State Management. This manipulation causes use after free. The attack may be initiated remotely. Upgrading to version 3.13.8 is able to mitigate this issue. The affected component should be upgraded. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2026-4390? +

CVE-2026-4390 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-4390? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2024-11139

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability exists that could allow local attackers to …

CVE-2025-1866

Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows Pointer Manipulation, potentially leading …

CVE-2025-2401

Buffer overflow vulnerability in Immunity Debugger affecting version 1.85, its exploitation could allow a local attacker to execute arbitrary code, …

CVE-2025-46333

z2d is a pure Zig 2D graphics library. Versions of z2d after `0.5.1` and up to and including `0.6.0`, when …

CVE-2025-6151

A vulnerability has been found in TP-Link TL-WR940N V4 and TL-WR841N V11. Affected by this issue is some unknown functionality …

CVE-2025-34096

A stack-based buffer overflow vulnerability exists in Easy File Sharing HTTP Server version 7.2. The flaw is triggered when a …

CVE-2026-4390