CVE-2026-23220 (GCVE-0-2026-23220)

Vulnerability from cvelistv5 – Published: 2026-02-18 14:53 – Updated: 2026-02-23 03:16
VLAI?
Title
ksmbd: fix infinite loop caused by next_smb2_rcv_hdr_off reset in error paths
Summary
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.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 943cebf9ea3415ddefcd670d24d8883e97ba3d60 , < fb3b66bd72deb5543addaefa67963b34fb163a7b (git)
Affected: be0f89d4419dc5413a1cf06db3671c9949be0d52 , < 5accdc5b7f28a81bbc5880ac0b8886e60c86e8c8 (git)
Affected: be0f89d4419dc5413a1cf06db3671c9949be0d52 , < f7b1c2f5642bbd60b1beef1f3298cbac81eb232c (git)
Affected: be0f89d4419dc5413a1cf06db3671c9949be0d52 , < 71b5e7c528315ca360a1825a4ad2f8ae48c5dc16 (git)
Affected: be0f89d4419dc5413a1cf06db3671c9949be0d52 , < 9135e791ec2709bcf0cda0335535c74762489498 (git)
Affected: be0f89d4419dc5413a1cf06db3671c9949be0d52 , < 010eb01ce23b34b50531448b0da391c7f05a72af (git)
Affected: 4b9b7ea1ffb1e34f01fa5726d0c184931b9ba565 (git)
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    Linux Linux Affected: 6.6
Unaffected: 0 , < 6.6 (semver)
Unaffected: 6.1.164 , ≤ 6.1.* (semver)
Unaffected: 6.6.125 , ≤ 6.6.* (semver)
Unaffected: 6.12.72 , ≤ 6.12.* (semver)
Unaffected: 6.18.11 , ≤ 6.18.* (semver)
Unaffected: 6.19.1 , ≤ 6.19.* (semver)
Unaffected: 7.0-rc1 , ≤ * (original_commit_for_fix)
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}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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