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CVE-2025-9820

Gnutls: stack-based buffer overflow in gnutls_pkcs11_token_init() function

Published: Jan 26, 2026Updated: May 12, 2026 Sources: CVE List NVD BDU csafCWE-121
4.0CVSSMEDIUM

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.

CVSS Vector Breakdown

AV:LAC:LPR:NUI:NS:UC:NI:NA:L
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low

Weaknesses

Affected Products

red hatcommercialUSOperating Systemsaka red hat
and 19 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

1 technique
Privilege Escalation
View detailed technique mapping

References

and 293 more references View all →

Timeline

Published
Jan 26, 2026
Last Updated
May 12, 2026

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