ssh: disallow gssapi-with-mic if GSSAPIWithMICConfig is not set

The ability to trigger the 'gssapi-with-mic' authentication method is
not properly gated by the presence of the GSSAPIWithMICConfig field of
the ServerConfig type. If this field is not set and a client sends a
'gssapi-with-mic' request, regardless of if the server advertises it,
the server will panic.

This issue was discovered and reported by Joern Schneewesiz, GitLab
Security Research Team.

Fixes CVE-2020-29652

Change-Id: Ie25de2766e442c8ab46680aae3ac89b0823cdeed
Trust: Roland Shoemaker <>
Run-TryBot: Roland Shoemaker <>
Reviewed-by: Filippo Valsorda <>
TryBot-Result: Go Bot <>
1 file changed
tree: 0183928d2fafb2f715756a35d986eeae89f39afa
  1. acme/
  2. argon2/
  3. bcrypt/
  4. blake2b/
  5. blake2s/
  6. blowfish/
  7. bn256/
  8. cast5/
  9. chacha20/
  10. chacha20poly1305/
  11. cryptobyte/
  12. curve25519/
  13. ed25519/
  14. hkdf/
  15. internal/
  16. md4/
  17. nacl/
  18. ocsp/
  19. openpgp/
  20. otr/
  21. pbkdf2/
  22. pkcs12/
  23. poly1305/
  24. ripemd160/
  25. salsa20/
  26. scrypt/
  27. sha3/
  28. ssh/
  29. tea/
  30. twofish/
  31. xtea/
  32. xts/
  33. .gitattributes
  34. .gitignore
  36. codereview.cfg
  39. go.mod
  40. go.sum

Go Cryptography

Go Reference

This repository holds supplementary Go cryptography libraries.


The easiest way to install is to run go get -u You can also manually git clone the repository to $GOPATH/src/

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Note that contributions to the cryptography package receive additional scrutiny due to their sensitive nature. Patches may take longer than normal to receive feedback.