CVE-2026-42010
Gnutls: gnutls: authentication bypass via nul character in username
CVSS Score
7.1
EPSS Score
1.1%
EPSS Percentile
60th
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.
| CWE | CWE-170 |
| Vendor | red hat |
| Product | red hat enterprise linux 10 |
| Published | May 7, 2026 |
| Last Updated | Jul 16, 2026 |
Stay Ahead of the Next One
Get instant alerts for red hat red hat enterprise linux 10
Be the first to know when new high vulnerabilities affecting red hat red hat enterprise linux 10 are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
Low
Availability
None
Affected Versions
Red Hat / Red Hat Enterprise Linux 10
All versions affected Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8
All versions affected Red Hat / Red Hat Enterprise Linux 8
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 9
All versions affected Red Hat / Red Hat Enterprise Linux 9
All versions affected Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.20
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.21
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.22
All versions affected Red Hat / Red Hat AI Inference Server 3.2
All versions affected Red Hat / Red Hat AI Inference Server 3.2
All versions affected Red Hat / Red Hat AI Inference Server 3.2
All versions affected Red Hat / Red Hat Discovery 2
All versions affected Red Hat / Red Hat Discovery 2
All versions affected Red Hat / Red Hat Hardened Images
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Enterprise Linux 6
All versions affected Red Hat / Red Hat Enterprise Linux 7
All versions affected Red Hat / Red Hat OpenShift Container Platform 4
All versions affected References
access.redhat.com: 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: https://access.redhat.com/errata/RHSA-2026:20613 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26319 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26409 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:29197 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:30004 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:30849 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:30850 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:32962 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:33125 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:34764 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:34788 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:34790 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:36004 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:36005 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:36006 access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-42010 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2467289 gnutls.org: https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-4 security.access.redhat.com: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42010.json
Credits
Red Hat would like to thank Joshua Rogers (AISLE Research Team) for reporting this issue.