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CVE-2026-42010

Gnutls: gnutls: authentication bypass via nul character in username

Published: May 7, 2026Updated: Jun 30, 2026 Sources: CVE List NVDCWE-170
7.1HIGH
NVD MITRE
EPSS Score
1.1%
Top 40.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

A flaw was found in gnutls. Servers configured with RSA-PSK (Rivest–Shamir–Adleman – Pre-Shared Key) wrongfully matched usernames containing a NUL character with truncated usernames. A remote attacker could exploit this by sending a specially crafted username, leading to an authentication bypass. This vulnerability allows an attacker to gain unauthorized access by circumventing the authentication process.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:HI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:LIntegrity
Low
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-170CWE-626

Affected Products

Red Hat
commercial·USaka redhat
Red Hat Enterprise Linux 10On-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 10.0 Extended Update SupportOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.8 Telecommunications Update ServiceOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.8 Update Services for SAP SolutionsOn-premOS
Operating Systems / linux-distro
gnu
oss-project·USaka g. nu
gnutls
OSS Libraries
and 13 more affected products View all →

Exploitability

Official Patch Available
Scannable·OpenVAS
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References

https://access.redhat.com/errata/RHSA-2026:13274
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:20611
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:20612
access.redhat.com
and 13 more references View all →
News mentions
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