Remote server crash via invalid PSK binder
Published Apr 9, 2026 · Updated Apr 9, 2026
Denial of service in GnuTLS in Red Hat Hardened Images allows remote attackers to crash TLS servers through a crafted ClientHello. In lib/ext/pre_shared_key.c, _gnutls_psk_recv_params() passes a null PSK credential pointer to server_recv_params(), which dereferences binder_algo after an invalid binder comparison. The server must issue a TLS 1.3 NewSessionTicket, and the client must resume with that ticket identity and a same-length but incorrect binder; the consequence is a repeatable process crash.
Summary
What happened
Denial of service in GnuTLS in Red Hat Hardened Images allows remote attackers to crash TLS servers through a crafted ClientHello. In lib/ext/pre_shared_key.c, _gnutls_psk_recv_params() passes a null PSK credential pointer to server_recv_params(), which dereferences binder_algo after an invalid binder comparison. The server must issue a TLS 1.3 NewSessionTicket, and the client must resume with that ticket identity and a same-length but incorrect binder; the consequence is a repeatable process crash.
The record
- CVE
- CVE-2026-1584
- Published
- Apr 9, 2026
- Updated
- Apr 9, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Hardened Images
- Classifications
- CWE-476, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 9, 2026CVE publishedPublication date reported by the CVE source.
- Apr 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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