CVE-2026-39835: golang.org/x/crypto/ssh is vulnerable to invoking server panic during CheckHostKey/Authenticate flow
(updated )
SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.
References
- access.redhat.com/errata/RHSA-2026:26546
- access.redhat.com/errata/RHSA-2026:26547
- access.redhat.com/security/cve/CVE-2026-39835
- bugzilla.redhat.com/show_bug.cgi?id=2480680
- github.com/advisories/GHSA-78mq-xcr3-xm33
- go.dev/cl/781660
- go.dev/issue/79563
- groups.google.com/g/golang-announce/c/a082jnz-LvI
- nvd.nist.gov/vuln/detail/CVE-2026-39835
- pkg.go.dev/vuln/GO-2026-5015
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39835.json
Code Behaviors & Features
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