Buffer overflow in Teamspeak 3 Server
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
EPSS: 0.004 (33.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.002
Affected products
- Teamspeak 3 Server — versions 3.13.0, 3.13.1, 3.13.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- vuldb.com/vuln/366314 (technical-description, vdb-entry)
- vuldb.com/vuln/366314/cti (signature, permissions-required)
- modzero.com/en/advisories/mz-26-01-teamspeak/ (related)
- files.teamspeak-services.com/docs/security/TS-SA-2026-001.html (related)
- www.teamspeak.com/en/downloads/ (patch)
Frequently asked questions
- What is CVE-2026-4390?
- CVE-2026-4390 is a medium-severity vulnerability in Teamspeak 3 Server, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.4/10. Published 2026-05-27.
- How severe is CVE-2026-4390?
- Medium severity. CVSS v3 base score is 5.4 out of 10.
- Is CVE-2026-4390 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.