CVE-2026-39829 PUBLISHED

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

Assigner: Go
Reserved: 07.04.2026 Published: 22.05.2026 Updated: 22.05.2026

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.

Product Status

Vendor golang.org/x/crypto
Product golang.org/x/crypto/ssh
Versions Default: unaffected
  • affected from 0 to 0.52.0 (excl.)

Credits

  • NCC Group Cryptography Services, sponsored by Teleport

References

Problem Types

  • CWE-1176: Inefficient CPU Computation