CVE-2026-23220
Published: Feb 18, 2026
Modified: Jun 2, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix infinite loop caused by next_smb2_rcv_hdr_off reset in error paths The problem occurs when a signed request fails smb2 signature verification check. In __process_request(), if check_sign_req() returns an error, set_smb2_rsp_status(work, STATUS_ACCESS_DENIED) is called. set_smb2_rsp_status() set work->next_smb2_rcv_hdr_off as zero. By resetting next_smb2_rcv_hdr_off to zero, the pointer to the next command in the chain is lost. Consequently, is_chained_smb2_message() continues to point to the same request header instead of advancing. If the header's NextCommand field is non-zero, the function returns true, causing __handle_ksmbd_work() to repeatedly process the same failed request in an infinite loop. This results in the kernel log being flooded with "bad smb2 signature" messages and high CPU usage. This patch fixes the issue by changing the return value from SERVER_HANDLER_CONTINUE to SERVER_HANDLER_ABORT. This ensures that the processing loop terminates immediately rather than attempting to continue from an invalidated offset.
| Vendor | Product | Versions |
|---|---|---|
Linux | Linux | affected 4b9b7ea1ffb1e34f01fa5726d0c184931b9ba565 - < 544adb0a6658ea1bff4064723761dbf05f95b1e2affected 943cebf9ea3415ddefcd670d24d8883e97ba3d60 - < fb3b66bd72deb5543addaefa67963b34fb163a7baffected be0f89d4419dc5413a1cf06db3671c9949be0d52 - < 5accdc5b7f28a81bbc5880ac0b8886e60c86e8c8affected be0f89d4419dc5413a1cf06db3671c9949be0d52 - < f7b1c2f5642bbd60b1beef1f3298cbac81eb232caffected be0f89d4419dc5413a1cf06db3671c9949be0d52 - < 71b5e7c528315ca360a1825a4ad2f8ae48c5dc16+4 more versions |
Linux | Linux | affected 6.6unaffected 0 - < 6.6unaffected 5.15.203 - <= 5.15.*unaffected 6.1.164 - <= 6.1.*unaffected 6.6.125 - <= 6.6.*+4 more versions |
References
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