Gnutls: gnutls: authentication bypass via nul character in username
Summary
| CVE | CVE-2026-42010 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-07 12:16:17 UTC |
| Updated | 2026-07-23 12:17:55 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 9.8 CRITICAL from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.010500000 probability, percentile 0.607070000 (date 2026-07-23)
Problem Types: CWE-170 | CWE-626 | CWE-170 Improper Null Termination | CWE-626 CWE-626 Null Byte Interaction Error (Poison Null Byte)
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | ADP | CVSS | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |
| 3.1 | [email protected] | Secondary | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |
| 3.1 | CNA | CVSS | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Gnu | Gnutls | - | All | All | All |
| Operating System | Redhat | Enterprise Linux | 10.0 | All | All | All |
| Operating System | Redhat | Enterprise Linux | 6.0 | All | All | All |
| Operating System | Redhat | Enterprise Linux | 7.0 | All | All | All |
| Operating System | Redhat | Enterprise Linux | 8.0 | All | All | All |
| Operating System | Redhat | Enterprise Linux | 9.0 | All | All | All |
| Application | Redhat | Hardened Images | - | All | All | All |
| Application | Redhat | Openshift Container Platform | 4.0 | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Enterprise Linux 10 | unaffected 0:3.8.10-4.el10_2 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | unaffected 0:3.8.9-9.el10_0.19 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | unaffected 0:3.6.16-8.el8_10.6 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | unaffected 0:3.6.16-8.el8_10.6 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | unaffected 0:3.8.10-4.el9_8 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | unaffected 0:3.8.10-4.el9_8 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9.2 Update Services For SAP Solutions | unaffected 0:3.7.6-21.el9_2.7 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9.4 Update Services For SAP Solutions | unaffected 0:3.8.3-4.el9_4.6 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | unaffected 0:3.8.3-6.el9_6.4 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.19 | unaffected 4.19.9.6.202607151909-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.20 | unaffected 4.20.9.6.202607010620-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.21 | unaffected 4.21.9.6.202607011303-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.22 | unaffected 4.22.9.8.202606301732-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951051 * rpm | Not specified |
| CNA | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951012 * rpm | Not specified |
| CNA | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951244 * rpm | Not specified |
| CNA | Red Hat | Red Hat Discovery 2 | unaffected 1782159791 * rpm | Not specified |
| CNA | Red Hat | Red Hat Discovery 2 | unaffected 1782166952 * rpm | Not specified |
| CNA | Red Hat | Red Hat Hardened Images | unaffected 3.8.13-1.hum1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525684 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525671 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525693 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525739 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 7 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 10 | unaffected 0:3.8.10-4.el10_2 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | unaffected 0:3.8.9-9.el10_0.19 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8 | unaffected 0:3.6.16-8.el8_10.6 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9 | unaffected 0:3.8.10-4.el9_8 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9.2 Update Services For SAP Solutions | unaffected 0:3.7.6-21.el9_2.7 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9.4 Update Services For SAP Solutions | unaffected 0:3.8.3-4.el9_4.6 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | unaffected 0:3.8.3-6.el9_6.4 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.19 | unaffected 4.19.9.6.202607151909-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.20 | unaffected 4.20.9.6.202607010620-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.21 | unaffected 4.21.9.6.202607011303-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.22 | unaffected 4.22.9.8.202606301732-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951051 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951012 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951244 * rpm | Not specified |
| ADP | Red Hat | Red Hat Discovery 2 | unaffected 1782159791 * rpm | Not specified |
| ADP | Red Hat | Red Hat Discovery 2 | unaffected 1782166952 * rpm | Not specified |
| ADP | Red Hat | Red Hat Hardened Images | unaffected 3.8.13-1.hum1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525684 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525671 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525693 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525739 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 7 | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/errata/RHSA-2026:30004 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36004 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-42010 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | Vendor Advisory |
| access.redhat.com/errata/RHSA-2026:30849 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:34764 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:20611 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:13274 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | Issue Tracking, Vendor Advisory |
| access.redhat.com/errata/RHSA-2026:20613 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36006 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:26319 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42010.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:32962 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:20612 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:29197 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| www.gnutls.org/security-new.html | [email protected] | www.gnutls.org | |
| access.redhat.com/errata/RHSA-2026:41921 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:40762 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:33125 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36005 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:34790 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:26409 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:30850 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:34788 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Red Hat would like to thank Joshua Rogers (AISLE Research Team) for reporting this issue. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-05-06T16:57:37.044Z | Reported to Red Hat. |
| CNA | 2026-04-29T00:00:00.000Z | Made public. |
| ADP | 2026-05-06T16:57:37.044Z | Reported to Red Hat. |
| ADP | 2026-04-29T00:00:00.000Z | Made public. |
Solutions
ADP: RHSA-2026:40762: Red Hat OpenShift Container Platform 4.19
ADP: RHSA-2026:34788: Red Hat OpenShift Container Platform 4.20
ADP: RHSA-2026:34764: Red Hat OpenShift Container Platform 4.21
ADP: RHSA-2026:34790: Red Hat OpenShift Container Platform 4.22
ADP: RHSA-2026:26409: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
ADP: RHSA-2026:20613: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10)
ADP: RHSA-2026:20611: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux BaseOS (v. 8)
ADP: RHSA-2026:33125: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4), Red Hat Enterprise Linux BaseOS AUS (v.8.4), Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)
ADP: RHSA-2026:30849: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6), Red Hat Enterprise Linux BaseOS AUS (v.8.6), Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6)
ADP: RHSA-2026:30850: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8), Red Hat Enterprise Linux BaseOS E4S (v.8.8), Red Hat Enterprise Linux BaseOS TUS (v.8.8)
ADP: RHSA-2026:41921: Red Hat Enterprise Linux AppStream E4S (v.9.2), Red Hat Enterprise Linux BaseOS E4S (v.9.2)
ADP: RHSA-2026:32962: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4)
ADP: RHSA-2026:30004: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6)
ADP: RHSA-2026:20612: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9)
ADP: RHSA-2026:36004: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:36005: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:36006: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:29197: Red Hat Discovery 2
ADP: RHSA-2026:13274: Red Hat Hardened Images
ADP: RHSA-2026:26319: Red Hat Update Infrastructure 5
There are currently no legacy QID mappings associated with this CVE.