CVE-2026-1584: Gnutls: gnutls: remote denial of service via crafted clienthello with invalid psk binder

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-09 · updated 2026-10-26
Weakness: CWE-476

Description

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.

Affected products

[UNKNOWN] gnutls: all versions
RedHat Hardened Images: all versions

References

https://access.redhat.com/errata/RHSA-2026:7477
https://access.redhat.com/security/cve/CVE-2026-1584
https://bugzilla.redhat.com/show_bug.cgi?id=2435258
https://access.redhat.com/errata/RHSA-2026:7477
https://access.redhat.com/security/cve/CVE-2026-1584
https://bugzilla.redhat.com/show_bug.cgi?id=2435258
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1584.json

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