CVE-2026-31536 (GCVE-0-2026-31536)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:30 – Updated: 2026-08-05 12:23
VLAI
Title
smb: server: let send_done handle a completion without IB_SEND_SIGNALED
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: server: let send_done handle a completion without IB_SEND_SIGNALED With smbdirect_send_batch processing we likely have requests without IB_SEND_SIGNALED, which will be destroyed in the final request that has IB_SEND_SIGNALED set. If the connection is broken all requests are signaled even without explicit IB_SEND_SIGNALED.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 24082642654f3e5149913946e89c00a297a8868f (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < e38b415c024bc3b6321bf8650dbf3f4aab8e74b3 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 9da82dc73cb03e85d716a2609364572367a5ff47 (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.18.11 , ≤ 6.18.* (semver)
Unaffected: 6.19.1 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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{
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          "programFiles": [
            "fs/smb/server/transport_rdma.c"
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    "dateReserved": "2026-03-09T15:48:24.113Z",
    "dateUpdated": "2026-08-05T12:23:21.869Z",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.


Detection rules are retrieved from Rulezet.