Vulnerability-Lookup

GHSA-RR3F-V8J5-MMR6

Vulnerability from github – Published: 2024-05-21 15:31 – Updated: 2025-04-30 15:30

Details

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

udp: fix race between close() and udp_abort()

Kaustubh reported and diagnosed a panic in udp_lib_lookup(). The root cause is udp_abort() racing with close(). Both racing functions acquire the socket lock, but udp{v6}_destroy_sock() release it before performing destructive actions.

We can't easily extend the socket lock scope to avoid the race, instead use the SOCK_DEAD flag to prevent udp_abort from doing any action when the critical race happens.

Diagnosed-and-tested-by: Kaustubh Pandey kapandey@codeaurora.org

Severity

4.7 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47248"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-362"
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    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-21T15:15:13Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nudp: fix race between close() and udp_abort()\n\nKaustubh reported and diagnosed a panic in udp_lib_lookup().\nThe root cause is udp_abort() racing with close(). Both\nracing functions acquire the socket lock, but udp{v6}_destroy_sock()\nrelease it before performing destructive actions.\n\nWe can\u0027t easily extend the socket lock scope to avoid the race,\ninstead use the SOCK_DEAD flag to prevent udp_abort from doing\nany action when the critical race happens.\n\nDiagnosed-and-tested-by: Kaustubh Pandey \u003ckapandey@codeaurora.org\u003e",
  "id": "GHSA-rr3f-v8j5-mmr6",
  "modified": "2025-04-30T15:30:42Z",
  "published": "2024-05-21T15:31:40Z",
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CVE-2021-47248 (GCVE-0-2021-47248)

Vulnerability from cvelistv5 – Published: 2024-05-21 14:19 – Updated: 2026-08-05 08:46

Title

udp: fix race between close() and udp_abort()

Summary

In the Linux kernel, the following vulnerability has been resolved: udp: fix race between close() and udp_abort() Kaustubh reported and diagnosed a panic in udp_lib_lookup(). The root cause is udp_abort() racing with close(). Both racing functions acquire the socket lock, but udp{v6}_destroy_sock() release it before performing destructive actions. We can't easily extend the socket lock scope to avoid the race, instead use the SOCK_DEAD flag to prevent udp_abort from doing any action when the critical race happens. Diagnosed-and-tested-by: Kaustubh Pandey <kapandey@codeaurora.org>

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/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 2024-05-23 18:04 UTC

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/e3c36c773aed0fef8…
https://git.kernel.org/stable/c/a0882f68f54f7a8b6…
https://git.kernel.org/stable/c/2f73448041bd0682d…
https://git.kernel.org/stable/c/5a88477c1c85e4baa…
https://git.kernel.org/stable/c/8729ec8a2238152a4…
https://git.kernel.org/stable/c/65310b0aff86980a0…
https://git.kernel.org/stable/c/a8b897c7bcd47f414…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < e3c36c773aed0fef8b1d3d555b43393ec564400f (git) Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < a0882f68f54f7a8b6308261acee9bd4faab5a69e (git) Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < 2f73448041bd0682d4b552cfd314ace66107f1ad (git) Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < 5a88477c1c85e4baa51e91f2d40f2166235daa56 (git) Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < 8729ec8a2238152a4afc212a331a6cd2c61aeeac (git) Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < 65310b0aff86980a011c7c7bfa487a333d4ca241 (git) Affected: 5d77dca82839ef016a93ad7acd7058b14d967752 , < a8b897c7bcd47f4147d066e22cc01d1026d7640e (git)
Linux	Linux	Affected: 4.9 Unaffected: 0 , < 4.9 (semver) Unaffected: 4.9.274 , ≤ 4.9.* (semver) Unaffected: 4.14.238 , ≤ 4.14.* (semver) Unaffected: 4.19.196 , ≤ 4.19.* (semver) Unaffected: 5.4.128 , ≤ 5.4.* (semver) Unaffected: 5.10.46 , ≤ 5.10.* (semver) Unaffected: 5.12.13 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)

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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.

Detection rules are retrieved from Rulezet.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.