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GHSA-97VV-3JQH-R766

Vulnerability from github – Published: 2024-03-15 21:30 – Updated: 2025-02-27 03:33

Details

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

xen-netback: take a reference to the RX task thread

Do this in order to prevent the task from being freed if the thread returns (which can be triggered by the frontend) before the call to kthread_stop done as part of the backend tear down. Not taking the reference will lead to a use-after-free in that scenario. Such reference was taken before but dropped as part of the rework done in 2ac061ce97f4.

Reintroduce the reference taking and add a comment this time explaining why it's needed.

This is XSA-374 / CVE-2021-28691.

Severity

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47111"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-03-15T21:15:06Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nxen-netback: take a reference to the RX task thread\n\nDo this in order to prevent the task from being freed if the thread\nreturns (which can be triggered by the frontend) before the call to\nkthread_stop done as part of the backend tear down. Not taking the\nreference will lead to a use-after-free in that scenario. Such\nreference was taken before but dropped as part of the rework done in\n2ac061ce97f4.\n\nReintroduce the reference taking and add a comment this time\nexplaining why it\u0027s needed.\n\nThis is XSA-374 / CVE-2021-28691.",
  "id": "GHSA-97vv-3jqh-r766",
  "modified": "2025-02-27T03:33:55Z",
  "published": "2024-03-15T21:30:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47111"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/107866a8eb0b664675a260f1ba0655010fac1e08"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6b53db8c4c14b4e7256f058d202908b54a7b85b4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/caec9bcaeb1a5f03f2d406305355c853af10c13e"
    }
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  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2021-47111 (GCVE-0-2021-47111)

Vulnerability from cvelistv5 – Published: 2024-03-15 20:14 – Updated: 2026-08-05 08:46

Title

xen-netback: take a reference to the RX task thread

Summary

In the Linux kernel, the following vulnerability has been resolved: xen-netback: take a reference to the RX task thread Do this in order to prevent the task from being freed if the thread returns (which can be triggered by the frontend) before the call to kthread_stop done as part of the backend tear down. Not taking the reference will lead to a use-after-free in that scenario. Such reference was taken before but dropped as part of the rework done in 2ac061ce97f4. Reintroduce the reference taking and add a comment this time explaining why it's needed. This is XSA-374 / CVE-2021-28691.

Severity

8.8 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-06-26 20:36 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6890 records in the last 180 days details

References

3 references

URL	Tags
https://git.kernel.org/stable/c/6b53db8c4c14b4e72…
https://git.kernel.org/stable/c/caec9bcaeb1a5f03f…
https://git.kernel.org/stable/c/107866a8eb0b66467…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 2ac061ce97f413bfbbdd768f7d2e0fda2e8170df , < 6b53db8c4c14b4e7256f058d202908b54a7b85b4 (git) Affected: 2ac061ce97f413bfbbdd768f7d2e0fda2e8170df , < caec9bcaeb1a5f03f2d406305355c853af10c13e (git) Affected: 2ac061ce97f413bfbbdd768f7d2e0fda2e8170df , < 107866a8eb0b664675a260f1ba0655010fac1e08 (git)
Linux	Linux	Affected: 5.5 Unaffected: 0 , < 5.5 (semver) Unaffected: 5.10.43 , ≤ 5.10.* (semver) Unaffected: 5.12.10 , ≤ 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.

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