# CVE-2026-121508: Use After Free in µD3TN

Status: published. Published: 2026-11-03. Updated: 2026-11-03.

Use-After-Free in µD3TN BPv6 Fragmenter Cleanup allows Unauthenticated Remote Attacker to Cause DoS on Allocation Failure

## Remediation

- fix: Upgrade to version 0.15.2 or above. (source: CNA: GitLab)

## Affected products and versions

- D3TN GmbH / µD3TN: ≥ 0; < 0.15.2 (affected, semver). Source: CNA: GitLab

## Severity and prioritization

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: GitLab

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-416

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://gitlab.com/d3tn/ud3tn/-/work_items/291 (CNA: GitLab)

## Provenance

- CNA: GitLab: https://www.cve.org/CVERecord?id=CVE-2026-121508; retrieved 2026-11-03; source updated 2026-11-03

Revision: e64878e357dcb56876fdeb58706f9fb956b4eb3d5d4938ad05626f2ac034259a

Canonical: https://y2.dev/cve/CVE-2026-121508

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