Deserialization in Golang Crypto

CVE-2026-39832

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of silently ignoring them.

Vulnerability class: Insecure Deserialization

EPSS: 0.006 (46.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-39832?
CVE-2026-39832 is a critical-severity vulnerability in Golang Crypto, classified under Deserialization of Untrusted Data. CVSS score: 9.1/10. Published 2026-05-22.
How severe is CVE-2026-39832?
Critical severity. CVSS v3 base score is 9.1 out of 10.