How severe is CVE-2026-4390?

CVE-2026-4390 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2026-4390 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-4390?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-4390 have an EU (EUVD) identifier?

Yes. CVE-2026-4390 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32580.

When was CVE-2026-4390 published?

CVE-2026-4390 was published on 2026-05-27 and last updated on 2026-06-17.

CVE-2026-4390

CVE-2026-4390 is a medium-severity vulnerability with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 5.5
CVSS v4: 5.3
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-32580
Weakness: CWE-119
Published: 2026-05-27
Last modified: 2026-06-17

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.

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.
How severe is CVE-2026-4390?: CVE-2026-4390 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2026-4390 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-4390?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-4390 have an EU (EUVD) identifier?: Yes. CVE-2026-4390 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32580.
When was CVE-2026-4390 published?: CVE-2026-4390 was published on 2026-05-27 and last updated on 2026-06-17.

References

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

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CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.

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