# CVE-2026-1584: Gnutls: gnutls: remote denial of service via crafted clienthello with invalid psk binder Status: published. Published: 2026-04-09. Updated: 2026-11-04. A flaw was found in gnutls. A remote, unauthenticated attacker can exploit this vulnerability by sending a specially crafted ClientHello message with an invalid Pre-Shared Key (PSK) binder value during the TLS handshake. This can lead to a NULL pointer dereference, causing the server to crash and resulting in a remote Denial of Service (DoS) condition. ## Remediation - workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. (source: CNA: redhat) - fix: RHSA-2026:7477: Red Hat Hardened Images (source: ADP: redhat-SADP) - workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. (source: ADP: redhat-SADP) ## Affected products and versions - / (gnutls): 0 (affected). Source: CNA: redhat - Red Hat / Red Hat Hardened Images (gnutls-main): ≥ 3.8.12-1.1.hum1; < * (unaffected, rpm). Source: CNA: redhat - Red Hat / Red Hat Enterprise Linux 10 (gnutls): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat Enterprise Linux 6 (gnutls): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat Enterprise Linux 7 (gnutls): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat Enterprise Linux 8 (gnutls): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat Enterprise Linux 9 (gnutls): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-8): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-9): Version range not reported. Source: CNA: redhat - Red Hat / Red Hat Hardened Images (gnutls-main): ≥ 3.8.12-1.1.hum1; < * (unaffected, rpm). Source: ADP: redhat-SADP - Red Hat / Red Hat Enterprise Linux 10 (gnutls): Version range not reported. Source: ADP: redhat-SADP - Red Hat / Red Hat Enterprise Linux 6 (gnutls): Version range not reported. Source: ADP: redhat-SADP - Red Hat / Red Hat Enterprise Linux 7 (gnutls): Version range not reported. Source: ADP: redhat-SADP - Red Hat / Red Hat Enterprise Linux 8 (gnutls): Version range not reported. Source: ADP: redhat-SADP - Red Hat / Red Hat Enterprise Linux 9 (gnutls): Version range not reported. Source: ADP: redhat-SADP - Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-8): Version range not reported. Source: ADP: redhat-SADP - Red Hat / Red Hat OpenShift Container Platform 4 (openshift/ose-rhel-coreos-9): Version range not reported. Source: ADP: redhat-SADP ## NVD configuration conditions Affected CPE matches depend on the following AND/OR and negation conditions: ```json [ { "negate": false, "nodes": [ { "cpeMatch": [ { "criteria": "cpe:2.3:a:gnu:gnutls:-:*:*:*:*:*:*:*", "vulnerable": true }, { "criteria": "cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*", "vulnerable": true } ], "negate": false, "operator": "OR" } ], "operator": "OR" } ] ``` ## Severity and prioritization - CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat - CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: ADP: redhat-SADP - CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: secalert@redhat.com - CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - CISA KEV: No listing in collected sources - EPSS: 1.32% as of 2026-11-04; percentile 70.98% - SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP - Weaknesses: CWE-476 ## Exploit evidence No exploit evidence in collected sources. This is not proof of no exploitation. ## References - https://access.redhat.com/errata/RHSA-2026:7477 (CNA: redhat; vendor-advisory, x_refsource_REDHAT) - https://access.redhat.com/security/cve/CVE-2026-1584 (CNA: redhat; vdb-entry, x_refsource_REDHAT) - https://bugzilla.redhat.com/show_bug.cgi?id=2435258 (CNA: redhat; issue-tracking, x_refsource_REDHAT) - https://access.redhat.com/security/cve/CVE-2026-1584 (ADP: redhat-SADP; vdb-entry, x_refsource_REDHAT) - https://bugzilla.redhat.com/show_bug.cgi?id=2435258 (ADP: redhat-SADP; issue-tracking, x_refsource_REDHAT) - https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1584.json (ADP: redhat-SADP; x_sadp-csaf-vex) - https://access.redhat.com/errata/RHSA-2026:7477 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT) - https://access.redhat.com/errata/RHSA-2026:7477 (secalert@redhat.com) - https://access.redhat.com/security/cve/CVE-2026-1584 (secalert@redhat.com; Vendor Advisory) - https://bugzilla.redhat.com/show_bug.cgi?id=2435258 (secalert@redhat.com; Issue Tracking, Vendor Advisory) - https://access.redhat.com/errata/RHSA-2026:7477 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c) - https://access.redhat.com/security/cve/CVE-2026-1584 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c; Vendor Advisory) - https://bugzilla.redhat.com/show_bug.cgi?id=2435258 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c; Issue Tracking, Vendor Advisory) - https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1584.json (0b0ca135-0b70-47e7-9f44-1890c2a1c46c) ## Provenance - CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-1584; retrieved 2026-11-04; source updated 2026-11-04 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-1584; retrieved 2026-11-05; source updated 2026-11-04 - FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-1584; retrieved 2026-11-04; source updated Not reported Revision: 1c0c35be4228a66b8d61fecf8494877fe2fadda8480860b0e6775823051ec536 Canonical: https://y2.dev/cve/CVE-2026-1584 ## Agent and API access Public CVE pages, Markdown, and JSON are free to read without an account or API key. - Public catalog: https://y2.dev/cve/index.json. 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