Vulnerability-Lookup

GHSA-4HWC-233G-5MV3

Vulnerability from github – Published: 2026-08-27 06:31 – Updated: 2026-08-27 06:31

Details

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

netfilter: flowtable: publish GC-visible tuple last

nf_flow_table_iterate() only treats original-direction tuple nodes as owning entries. Publishing the original node first lets GC observe and free a flow while flow_offload_add() is still inserting the reply node. Publish the reply node first and the original node last so GC never sees a partially installed flow.

KASAN can trigger slab-use-after-free read and write reports in the flowtable/rhashtable path (rht_deferred_worker, jhash, flow_offload_del, flow_offload_lookup, etc.).

Severity

9.8 (Critical)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-74746"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-26T15:16:53Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: flowtable: publish GC-visible tuple last\n\nnf_flow_table_iterate() only treats original-direction tuple nodes as\nowning entries. Publishing the original node first lets GC observe and\nfree a flow while flow_offload_add() is still inserting the reply node.\nPublish the reply node first and the original node last so GC never\nsees a partially installed flow.\n\nKASAN can trigger slab-use-after-free read and write reports in the\nflowtable/rhashtable path (rht_deferred_worker, jhash, flow_offload_del,\nflow_offload_lookup, etc.).",
  "id": "GHSA-4hwc-233g-5mv3",
  "modified": "2026-08-27T06:31:30Z",
  "published": "2026-08-27T06:31:30Z",
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      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74746"
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}

CVE-2026-74746 (GCVE-0-2026-74746)

Vulnerability from cvelistv5 – Published: 2026-08-26 14:36 – Updated: 2026-10-16 19:26

Title

netfilter: flowtable: publish GC-visible tuple last

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable: publish GC-visible tuple last nf_flow_table_iterate() only treats original-direction tuple nodes as owning entries. Publishing the original node first lets GC observe and free a flow while flow_offload_add() is still inserting the reply node. Publish the reply node first and the original node last so GC never sees a partially installed flow. KASAN can trigger slab-use-after-free read and write reports in the flowtable/rhashtable path (rht_deferred_worker, jhash, flow_offload_del, flow_offload_lookup, etc.).

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: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-16 19:16 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6664 records in the last 180 days details

References

8 references

URL	Tags
https://git.kernel.org/stable/c/0a00254585827f169…
https://git.kernel.org/stable/c/be345dcbddb4643a5…
https://git.kernel.org/stable/c/211ee5d998d92a7d5…
https://git.kernel.org/stable/c/d37917e7bebe078f3…
https://git.kernel.org/stable/c/972fdf7c4f5c282a2…
https://git.kernel.org/stable/c/d9d3050a70efe217e…
https://git.kernel.org/stable/c/d16b71231e65cb05d…
https://git.kernel.org/stable/c/2014ac62df9d45bb9…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < 0a00254585827f1695aa2700114af622ea754cfa (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < be345dcbddb4643a54252b954af974b16eda8f91 (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < 211ee5d998d92a7d548811939c65942d06c146e4 (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < d37917e7bebe078f3c17e47fd6fc1c9f6e8497b2 (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < 972fdf7c4f5c282a239c88fea614b056c33dc025 (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < d9d3050a70efe217e73a0751e55fdae6a7092620 (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < d16b71231e65cb05daea2b45701fcf09cef041e7 (git) Affected: ac2a66665e231847cab11b8c8e844ce43207dd2e , < 2014ac62df9d45bb9a004a043e85df7be09ed780 (git)
Linux	Linux	Affected: 4.16 Unaffected: 0 , < 4.16 (semver) Unaffected: 5.10.266 , ≤ 5.10.* (semver) Unaffected: 5.15.217 , ≤ 5.15.* (semver) Unaffected: 6.1.184 , ≤ 6.1.* (semver) Unaffected: 6.6.153 , ≤ 6.6.* (semver) Unaffected: 6.12.105 , ≤ 6.12.* (semver) Unaffected: 6.18.46 , ≤ 6.18.* (semver) Unaffected: 7.1.10 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

Show details on NVD website

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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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