In the Linux kernel, the following vulnerability has been resolved: smb: client: fix server->total_read for compound encrypted PDUs In receive_encrypted_standard(), server->total_read is left at the full decrypted frame size when walking sub-PDUs of a compound encrypted frame. As a result, cifs_handle_standard() passes this full size to smb2_check_message(), causing the PDU length guards to incorrectly validate the entire compound frame instead of the current sub-PDU. This allows truncated non-last sub-PDUs to bypass length validation, leading to out-of-bounds reads in smb2_get_data_area_len(). Fix this by setting server->total_read to the true length of the current sub-PDU: next_cmd for non-last sub-PDUs, and the remaining pdu_length for the last one.
Fix
Microsoft's update · Critical
- Release Notes — azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 · build 6.6.158.1-1
From the 2026-Oct release note of Microsoft's Security Update Guide, revised 2026-10-28.
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 2
- StatusReceived → PublishedNVD modified 2026-10-19 09:14
- First seenunscoredNVD modified 2026-10-19 10:18
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 6
- https://git.kernel.org/stable/c/282b72f9a7ef31296c48366db4128882999cc048
- https://git.kernel.org/stable/c/8703539d22fdbc13dd2db090ee199c3a427b8ea0
- https://git.kernel.org/stable/c/a46eb242e9eef3a3897d166748b23303c516e870
- https://git.kernel.org/stable/c/e78fc1d240b27349b45a0f1c3e3c2c401d7e230d
- https://git.kernel.org/stable/c/ebb8a075fdc7af3d196a4f158a0e18dbc394c0e3
- https://git.kernel.org/stable/c/f73726b83e4756fdaa099e1bc1143293bd57ad79