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CVE

DEBIAN-CVE-2026-39831

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag.
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CVE

DEBIAN-CVE-2026-39831

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag.

The Verify() method for FIDO/U2F security key types (sk-ecdsa-sha2-nistp256@openssh.com, sk-ssh-ed25519@openssh.com) did not check the User Presence flag. Signatures generated without physical touch were accepted, allowing unattended use of a hardware security key. To restore the previous behavior, return a "no-touch-required" extension in Permissions.Extensions from PublicKeyCallback.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
-
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
C
H
U
-

Related Resources

No items found.

References

https://security-tracker.debian.org/tracker/CVE-2026-39831

Severity

9.1

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
9.1
EPSS Probability
0%
EPSS Percentile
0%
Introduced Version
0
Fix Available

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