CVE-2025-9820
Severity CVSS v4.0:
Pending analysis
Type:
CWE-121
Stack-based Buffer Overflow
Publication date:
26/01/2026
Last modified:
26/01/2026
Description
A flaw was found in the GnuTLS library, specifically in the gnutls_pkcs11_token_init() function that handles PKCS#11 token initialization. When a token label longer than expected is processed, the function writes past the end of a fixed-size stack buffer. This programming error can cause the application using GnuTLS to crash or, in certain conditions, be exploited for code execution. As a result, systems or applications relying on GnuTLS may be vulnerable to a denial of service or local privilege escalation attacks.
Impact
Base Score 3.x
4.00
Severity 3.x
MEDIUM
References to Advisories, Solutions, and Tools
- https://access.redhat.com/security/cve/CVE-2025-9820
- https://bugzilla.redhat.com/show_bug.cgi?id=2392528
- https://gitlab.com/gnutls/gnutls/-/commit/1d56f96f6ab5034d677136b9d50b5a75dff0faf5
- https://gitlab.com/gnutls/gnutls/-/issues/1732
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2025-11-18
- http://www.openwall.com/lists/oss-security/2025/11/20/2



