CVE-2026-39829highCWE-1284

CVE-2026-39829: high-severity vulnerability in golang.org/x/crypto/ssh

Invoking pathological RSA/DSA parameters may cause DoS in golang.org/x/crypto/ssh

Published 22 May 2026 · Updated 18 Sep 2026

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.5%

exploitation probability

0.5%top 60% of all CVEs

observed exploitation

nono source reports it

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

golang.org/x/crypto · golang.org/x/crypto/ssh

Related 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%

References