What’s Vulnerable › Vulnerabilities

CVE-2026-42508: Invoking auth bypass via unenforced @revoked status in golang.org/x/crypto/ssh/knownhosts

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 6.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-05-22 · updated 2026-09-15
• Weakness: CWE-295

Description

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

Affected products

• golang.org/x/crypto/ssh: before 0.52.0 — fixed in 0.52.0
• Golang.Org/X/Crypto: before 0.52.0 — fixed in 0.52.0

How to fix

Upgrade to a fixed version: golang.org/x/crypto/ssh 0.52.0; Golang.Org/X/Crypto 0.52.0. Check the vendor advisory for mitigations.

References

• https://go.dev/cl/781220
• https://go.dev/issue/79568
• https://groups.google.com/g/golang-announce/c/a082jnz-LvI
• https://pkg.go.dev/vuln/GO-2026-5021
• https://access.redhat.com/errata/RHSA-2026:23262
• https://access.redhat.com/errata/RHSA-2026:23264
• https://access.redhat.com/errata/RHSA-2026:26546
• https://access.redhat.com/errata/RHSA-2026:26547
• https://access.redhat.com/errata/RHSA-2026:35833
• https://access.redhat.com/errata/RHSA-2026:36648
• https://access.redhat.com/errata/RHSA-2026:36651
• https://access.redhat.com/errata/RHSA-2026:36796

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