PT-2026-42710 · Openssh · Openssh

Published 2026-05-22 · Updated 2026-05-22 · CVE-2026-39831

Positive Technologies (AI Summary)

CVSS v3.1

9.1

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Name of the Vulnerable Software and Affected Versions The product name cannot be determined (affected versions not specified)

Description The Verify() method for FIDO/U2F security key types [e-mail] and [e-mail] failed to check the User Presence flag. This allows signatures generated without physical touch to be accepted, enabling the unattended use of a hardware security key.

Recommendations Return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback to restore the previous behavior.

Fix

Related Identifiers

CVE-2026-39831

GO-2026-5019

Affected Products

Openssh

References · 6

• https://osv.dev/vulnerability/GO-2026-5019 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39831 · Security Note
• https://groups.google.com/g/golang-announce/c/a082jnz-LvI · Note
• https://go.dev/cl/781662 · Note
• https://go.dev/issue/79566 · Note
• https://pkg.go.dev/vuln/GO-2026-5019 · Note