Medium severity4.0OSV Advisory· Published Jan 26, 2026· Updated May 12, 2026
CVE-2025-9820
CVE-2025-9820
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.
Affected products
1- Range: 3.6.12, 3.6.13, 3.6.14, …
Patches
0No patches discovered yet.
Vulnerability mechanics
AI mechanics synthesis has not run for this CVE yet.
References
16- www.openwall.com/lists/oss-security/2025/11/20/2nvd
- access.redhat.com/errata/RHSA-2026:13812nvd
- access.redhat.com/errata/RHSA-2026:3477nvd
- access.redhat.com/errata/RHSA-2026:4188nvd
- access.redhat.com/errata/RHSA-2026:4655nvd
- access.redhat.com/errata/RHSA-2026:4943nvd
- access.redhat.com/errata/RHSA-2026:5585nvd
- access.redhat.com/errata/RHSA-2026:5606nvd
- access.redhat.com/errata/RHSA-2026:7329nvd
- access.redhat.com/errata/RHSA-2026:7477nvd
- access.redhat.com/security/cve/CVE-2025-9820nvd
- bugzilla.redhat.com/show_bug.cginvd
- cert-portal.siemens.com/productcert/html/ssa-032379.htmlnvd
- gitlab.com/gnutls/gnutls/-/commit/1d56f96f6ab5034d677136b9d50b5a75dff0faf5nvd
- gitlab.com/gnutls/gnutls/-/issues/1732nvd
- www.gnutls.org/security-new.htmlnvd
News mentions
1- Siemens SIMATICCISA Alerts