Vulnerability-Lookup

GHSA-X6H6-973G-Q656

Vulnerability from github – Published: 2024-10-21 15:32 – Updated: 2025-11-04 00:31

Details

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

nbd: fix race between timeout and normal completion

If request timetout is handled by nbd_requeue_cmd(), normal completion has to be stopped for avoiding to complete this requeued request, other use-after-free can be triggered.

Fix the race by clearing NBD_CMD_INFLIGHT in nbd_requeue_cmd(), meantime make sure that cmd->lock is grabbed for clearing the flag and the requeue.

Severity

7.0 (High)


                  
                    CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2024-49855"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-10-21T13:15:06Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnbd: fix race between timeout and normal completion\n\nIf request timetout is handled by nbd_requeue_cmd(), normal completion\nhas to be stopped for avoiding to complete this requeued request, other\nuse-after-free can be triggered.\n\nFix the race by clearing NBD_CMD_INFLIGHT in nbd_requeue_cmd(), meantime\nmake sure that cmd-\u003elock is grabbed for clearing the flag and the\nrequeue.",
  "id": "GHSA-x6h6-973g-q656",
  "modified": "2025-11-04T00:31:39Z",
  "published": "2024-10-21T15:32:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-49855"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5236ada8ebbd9e7461f17477357582f5be4f46f7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6e73b946a379a1dfbb62626af93843bdfb53753d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9a74c3e6c0d686c26ba2aab66d15ddb89dc139cc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9c25faf72d780a9c71081710cd48759d61ff6e9b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c9ea57c91f03bcad415e1a20113bdb2077bcf990"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"
    }
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  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2024-49855 (GCVE-0-2024-49855)

Vulnerability from cvelistv5 – Published: 2024-10-21 12:18 – Updated: 2026-08-05 11:40

Title

nbd: fix race between timeout and normal completion

Summary

In the Linux kernel, the following vulnerability has been resolved: nbd: fix race between timeout and normal completion If request timetout is handled by nbd_requeue_cmd(), normal completion has to be stopped for avoiding to complete this requeued request, other use-after-free can be triggered. Fix the race by clearing NBD_CMD_INFLIGHT in nbd_requeue_cmd(), meantime make sure that cmd->lock is grabbed for clearing the flag and the requeue.

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-10-21 12:56 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 54/100 over 6633 records in the last 180 days details

References

6 references

URL	Tags
https://git.kernel.org/stable/c/9c25faf72d780a9c7…
https://git.kernel.org/stable/c/6e73b946a379a1dfb…
https://git.kernel.org/stable/c/5236ada8ebbd9e746…
https://git.kernel.org/stable/c/9a74c3e6c0d686c26…
https://git.kernel.org/stable/c/c9ea57c91f03bcad4…
https://lists.debian.org/debian-lts-announce/2025…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 2895f1831e911ca87d4efdf43e35eb72a0c7e66e , < 9c25faf72d780a9c71081710cd48759d61ff6e9b (git) Affected: 2895f1831e911ca87d4efdf43e35eb72a0c7e66e , < 6e73b946a379a1dfbb62626af93843bdfb53753d (git) Affected: 2895f1831e911ca87d4efdf43e35eb72a0c7e66e , < 5236ada8ebbd9e7461f17477357582f5be4f46f7 (git) Affected: 2895f1831e911ca87d4efdf43e35eb72a0c7e66e , < 9a74c3e6c0d686c26ba2aab66d15ddb89dc139cc (git) Affected: 2895f1831e911ca87d4efdf43e35eb72a0c7e66e , < c9ea57c91f03bcad415e1a20113bdb2077bcf990 (git) Affected: cdf62c535a9bfd5ff0eef4b91669da39d8abc0c3 (git) Affected: 5171ef20bae852ff38f4cfdb368bcdcc744776d0 (git) Affected: 5.17.15 , < 5.18 (semver) Affected: 5.18.4 , < 5.19 (semver)
Linux	Linux	Affected: 5.19 Unaffected: 0 , < 5.19 (semver) Unaffected: 6.1.113 , ≤ 6.1.* (semver) Unaffected: 6.6.54 , ≤ 6.6.* (semver) Unaffected: 6.10.13 , ≤ 6.10.* (semver) Unaffected: 6.11.2 , ≤ 6.11.* (semver) Unaffected: 6.12 , ≤ * (original_commit_for_fix)

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                "id": "CVE-2024-49855",
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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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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GHSA-X6H6-973G-Q656

CVE-2024-49855 (GCVE-0-2024-49855)

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