id: GO-2021-0356
modules:
    - module: golang.org/x/crypto
      versions:
        - fixed: 0.0.0-20220314234659-1baeb1ce4c0b
      vulnerable_at: 0.0.0-20220314234646-fcc990c556fe
      packages:
        - package: golang.org/x/crypto/ssh
          symbols:
            - ServerConfig.AddHostKey
summary: Denial of service via crafted Signer in golang.org/x/crypto/ssh
description: |-
    Attackers can cause a crash in SSH servers when the server has been configured
    by passing a Signer to ServerConfig.AddHostKey such that
    1) the Signer passed to AddHostKey does not implement AlgorithmSigner, and
    2) the Signer passed to AddHostKey returns a key of type “ssh-rsa” from its
    PublicKey method.

    Servers that only use Signer implementations provided by the ssh package are
    unaffected.
published: 2022-04-25T20:38:40Z
cves:
    - CVE-2022-27191
ghsas:
    - GHSA-8c26-wmh5-6g9v
references:
    - fix: https://go.dev/cl/392355
    - fix: https://go.googlesource.com/crypto/+/1baeb1ce4c0b006eff0f294c47cb7617598dfb3d
    - web: https://groups.google.com/g/golang-announce
    - web: https://groups.google.com/g/golang-announce/c/-cp44ypCT5s