What happened
wolfSSH’s key exchange state machine can be manipulated to leak the client’s password in the clear, trick the client to send a bogus signature, or trick the client into skipping user authentication. This affects client applications with wolfSSH version 1.4.21 and earlier. Users of wolfSSH must update or apply the fix patch and it’s recommended to update credentials used. This fix is also recommended for wolfSSH server applications. While there aren’t any specific attacks on server applications, the same defect is present. Thanks to Aina Toky Rasoamanana of Valeo and Olivier Levillain of Telecom SudParis for the report.
Affected versions
wolfSSH: before 1.4.22 (semver) Fixed: See vendor advisory.
Why it matters
Review the vendor advisory and exposure of the affected product to determine operational impact.
Detection & mitigation
- Apply vendor-provided updates or mitigations.
- Review affected product exposure and access logs.
Public PoC references
No public PoC reference has passed the current publication threshold.