NewApp Monitoring is liveSign up free
AgentbeamBeta
Open-source package vulnerability · Go

CVE-2026-39831: golang.org/x/crypto: FIDO/U2F security key physical presence check can be bypassed

criticalCVSS 3.1 9.1GHSA-89gr-r52h-f8rx

The Verify() method for FIDO/U2F security key types ([email protected], [email protected]) 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.

Published Jun 25, 2026 · Updated Jul 7, 2026

Affected packages

golang.org/x/crypto

Ecosystem
Go
Affected
< 0.52.0
Fixed in
0.52.0
Check
go list -m golang.org/x/crypto

Advisory details

From the GitHub Advisory Database (CC BY 4.0).

The Verify() method for FIDO/U2F security key types ([email protected], [email protected]) 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.

References

How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology

More Go vulnerabilities

All Go entries