CVE-2026-90169 PUBLISHED

ksmbd: free preauth sessions on connection teardown

Assigner: Linux
Reserved: 11.09.2026 Published: 17.09.2026 Updated: 17.09.2026

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: free preauth sessions on connection teardown

SMB3.1.1 multichannel binding preserves the preauthentication hash in a preauth_session between the NTLM negotiate and authenticate requests. The binding NTLM negotiate allocates this object and returns STATUS_MORE_PROCESSING_REQUIRED. If the client disconnects before it sends the authenticate request, neither the authenticate nor error cleanup paths free the object.

Release any remaining preauthentication sessions when tearing down the connection. Initialize the list when allocating the connection so that this cleanup is safe regardless of the negotiated dialect.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from f5a544e3bab78142207e0242d22442db85ba1eff to effcf48d79d8aa53113d8289e140746f25ceb62c (excl.)
  • affected from f5a544e3bab78142207e0242d22442db85ba1eff to b62b1ebb25f0a19067ed5b1a86036b2dc98be44f (excl.)
  • affected from f5a544e3bab78142207e0242d22442db85ba1eff to a41a98ee16ae038751b6639decadaa3ce15ca18a (excl.)
  • affected from f5a544e3bab78142207e0242d22442db85ba1eff to 8e2ebc77678832e981adc008d25cd8f67d08ebc4 (excl.)
  • affected from f5a544e3bab78142207e0242d22442db85ba1eff to 06c7b1d731bc105a8644f1b70165ba8b9416cbab (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 5.15 is affected
  • unaffected from 0 to 5.15 (excl.)
  • unaffected from 6.6.157 to 6.6.* (incl.)
  • unaffected from 6.12.110 to 6.12.* (incl.)
  • unaffected from 6.18.52 to 6.18.* (incl.)
  • unaffected from 7.2.6 to 7.2.* (incl.)
  • unaffected from 7.3-rc1 to * (incl.)

References