CVE-2026-39830 PUBLISHED

Invoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/ssh

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

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

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-833: Deadlock