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. 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.

• CWE-862

• https://go.dev/cl/781662Issue Tracking
• https://go.dev/issue/79566Issue Tracking
• https://groups.google.com/g/golang-announce/c/a082jnz-LvIMailing List
• https://pkg.go.dev/vuln/GO-2026-5019Vendor Advisory

Published

May 22, 2026

Last Modified

Jul 23, 2026

Status

Analyzed

• Uncovering a hidden BOLA in Appsmith's snapshot logicStrix autonomously discovered a BOLA/IDOR vulnerability in Appsmith's snapshot deletion path.
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• CVE-2026-39827An authenticated SSH client that repeatedly opened channels …6.5
• CVE-2026-39828When an SSH server authentication callback returned PartialS…6.3
• CVE-2026-39829The RSA and DSA public key parsers did not enforce size limi…7.5
• CVE-2026-3983A security flaw has been discovered in Campcodes Division Re…3.5
• CVE-2026-39830A malicious SSH peer could send unsolicited global request r…9.1
• CVE-2026-39832When adding a key to a remote agent constraint extensions su…9.1
• CVE-2026-39833The in-memory keyring returned by NewKeyring() silently acce…9.1
• CVE-2026-39834When writing data larger than 4GB in a single Write call on …9.1
• CVE-2026-39835SSH servers which use CertChecker as a public key callback w…5.3
• CVE-2026-39836The Dial and LookupPort functions panic on Windows when prov…7.5
• CVE-2026-39837Improper neutralization of Script-Related HTML tags in a web…5.4