CVE-2026-78662: high-severity vulnerability in golang.org/x/crypto/ssh
Prevent DoS on deadlocked undecided channel in golang.org/x/crypto/ssh
Published · Updated
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.4%
exploitation probability
0.4%top 63% of all CVEs
observed exploitation
nono source reports it
Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
golang.org/x/crypto · golang.org/x/crypto/sshRelated CVEs — golang.org/x/crypto/ssh
In the same product, most dangerous first.
CVE-2024-45337CRITICALMisuse of connection.serverAuthenticate may cause authorization bypass in golang.org/x/cryptoEPSS 3.2%CVE-2025-22869HIGHPotential denial of service in golang.org/x/cryptoEPSS 0.9%CVE-2026-39830CRITICALInvoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/sshEPSS 0.7%CVE-2026-39834CRITICALInvoking infinite loop on large channel writes in golang.org/x/crypto/sshEPSS 0.6%CVE-2025-58181MEDIUMUnbounded memory consumption in golang.org/x/crypto/sshEPSS 0.6%CVE-2026-46595CRITICALInvoking VerifiedPublicKeyCallback permissions skip enforcement in golang.org/x/crypto/sshEPSS 0.6%