CVE-2026-39833: critical vulnerability in golang.org/x/crypto/ssh/agent
Invoking key constraints not enforced in golang.org/x/crypto/ssh/agent
Published · Updated
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 0.5%
exploitation probability
0.5%top 59% of all CVEs
observed exploitation
nono source reports it
The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
golang.org/x/crypto · golang.org/x/crypto/ssh/agentRelated CVEs — golang.org/x/crypto/ssh/agent
In the same product, most dangerous first.
CVE-2026-39832CRITICALInvoking agent constraints dropped when forwarding keys in golang.org/x/crypto/ssh/agentEPSS 0.7%CVE-2025-47913HIGHPotential denial of service in golang.org/x/crypto/ssh/agentEPSS 0.7%CVE-2025-47914MEDIUMMalformed constraint may cause denial of service in golang.org/x/crypto/ssh/agentEPSS 0.5%CVE-2026-46598MEDIUMInvoking pathological inputs can lead to client panic in golang.org/x/crypto/ssh/agentEPSS 0.4%