CVE-2026-88648

low

Incomplete X.509 implementation in GnuTLS v3.8.13 allows attackers controlling a subordinate Certificate Authority to bypass cross-domain PKI restrictions and…

In GnuTLS v3.8.13, an excluded msUPN/SRV otherName is never checked. NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.

CVSS

3.7

3.7 (CVSS v3.1)

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

Severity source: NVD CVSS v3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)

Timeline (UTC)

Published: 2026-10-08 19:20

Modified: 2026-11-04 05:19

NVD status: Awaiting Analysis

Last synced 22 hours ago

Verified against the source API 2026-11-04 05:28 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

Not reported by the source (unknown — not "none").

Weakness classification (CWE)

CWE-295

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

https://gist.github.com/lkloliver/1f2a97cb8d0b31aa27b6bd0354358d7d cve@mitre.org
https://gitlab.com/gnutls/gnutls/-/blob/e2169a87c7fb91935c2845088204b102baed4c5f/SECURITY.... cve@mitre.org
https://gitlab.com/gnutls/gnutls/-/work_items/1965 cve@mitre.org
https://www.rfc-editor.org/rfc/rfc5280#section-4.2.1.10 cve@mitre.org
https://www.rfc-editor.org/rfc/rfc5280#section-6.1.4 cve@mitre.org
https://github.com/lkloliver/poc/tree/main/CVE-2026-88648 af854a3a-2127-422b-91ae-364da2661108

Data sources

NVD CVE API 2.0 — fetched 2026-11-04 05:28 UTC · record ↗

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