Summary

A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning the attack complexity high.

Products Affected

• Brocade ASCG base OS (OVA deployment) before 3.4.0

Products Not Affected

• Brocade Fabric OS
  [VEX Justification: Inline_mitigations_already_exist]
• Brocade SANNav standard deployment
  [VEX Justification: Vulnerable_code_not_in_execute_path]
• Brocade SANnav base OS (OVA Deployment) before 3.0.0
  [VEX Justification: Code_not_present]
• Brocade ASCG Standard Deployment
  [VEX Justification: Vulnerable_code_not_in_execute_path]

Solution

• Security update is provided in Brocade ASCG base OS (OVA Deployment) 3.4.0
• Although Brocade SANnav base OS (OVA Deployment) is not exploitable, Security update provided in Brocade SANnav base OS (OVA Deployment) 3.0.0
• Although Brocade Fabric OS is not exploitable, Security update provided in Brocade Fabric OS 10.0

Revision History

Disclaimer

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