Medium severity · published Jan 26, 2026
CVE-2025-9820
Gnutls: stack-based buffer overflow in gnutls_pkcs11_token_init() function
4.0
CVSS
0.2%
EPSS
No
On KEV
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
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CM
Cert Manager support for Red Hat OpenShift release 1.18 · Red Hat
All versions, or not specified · source: vendor
RB
RHEL-8 based Middleware Containers · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Ceph Storage 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Discovery 2 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 6 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 9 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Insights proxy 1.5 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat OpenShift Container Platform 4 · Red Hat
All versions, or not specified · source: vendor
Affected product
CM
Cert Manager support for Red Hat OpenShift release 1.18
Red Hat
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-9820
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-9820
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:13812
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:3477
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:4188
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:4655
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:4943
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:5585
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