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EUVD-2026-364804

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 08:34

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T08:34:11.265529+00:00",
  "id": "EUVD-2026-364804"
}

CVE-2026-43499 (GCVE-0-2026-43499)

Vulnerability from cvelistv5 – Published: 2026-05-21 12:17 – Updated: 2026-09-08 08:48

Title

rtmutex: Use waiter::task instead of current in remove_waiter()

Summary

In the Linux kernel, the following vulnerability has been resolved: rtmutex: Use waiter::task instead of current in remove_waiter() remove_waiter() is used by the slowlock paths, but it is also used for proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from futex_requeue(). In the latter case waiter::task is not current, but remove_waiter() operates on current for the dequeue operation. That results in several problems: 1) the rbtree dequeue happens without waiter::task::pi_lock being held 2) the waiter task's pi_blocked_on state is not cleared, which leaves a dangling pointer primed for UAF around. 3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter task Use waiter::task instead of current in all related operations in remove_waiter() to cure those problems. [ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the changelog ]

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: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-22 03:55 UTC

CWE

CWE-416 - Use After Free

Assigner

Linux mitre root Scorecard

References

10 references

URL	Tags
https://git.kernel.org/stable/c/f3fa3424bceb128d2…
https://git.kernel.org/stable/c/838ce5cb5d93c3ab8…
https://git.kernel.org/stable/c/d8cce4773c2b23d81…
https://git.kernel.org/stable/c/8a1fc8d698ac5e591…
https://git.kernel.org/stable/c/6d52dfcb2a5db86e3…
https://git.kernel.org/stable/c/3fb7394a837740770…
https://git.kernel.org/stable/c/88614876370aac8ad…
https://git.kernel.org/stable/c/3bfdc63936dd47731…
http://www.openwall.com/lists/oss-security/2026/0…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

5 products

Vendor	Product	Version
Linux	Linux	Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < f3fa3424bceb128d2be4b3745506b22844b87db7 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 838ce5cb5d93c3ab8b27e75bc6ad905a94b752fd (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < d8cce4773c2b23d819baf5abedc62f7b430e8745 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 8a1fc8d698ac5e5916e3082a0f74450d71f9611f (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 6d52dfcb2a5db86e346cf51f8fcf2071b8085166 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 3fb7394a837740770f0d6b4b30567e60786a63f2 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 88614876370aac8ad1050ad785a4c095ba17ac11 (git) Affected: 8161239a8bcce9ad6b537c04a1fa3b5c68bae693 , < 3bfdc63936dd4773109b7b8c280c0f3b5ae7d349 (git)
Linux	Linux	Affected: 2.6.39 Unaffected: 0 , < 2.6.39 (semver) Unaffected: 5.10.261 , ≤ 5.10.* (semver) Unaffected: 5.15.212 , ≤ 5.15.* (semver) Unaffected: 6.1.175 , ≤ 6.1.* (semver) Unaffected: 6.6.140 , ≤ 6.6.* (semver) Unaffected: 6.12.86 , ≤ 6.12.* (semver) Unaffected: 6.18.27 , ≤ 6.18.* (semver) Unaffected: 7.0.4 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)

Show details on NVD website

JSON

To clipboard

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        "providerMetadata": {
          "dateUpdated": "2026-09-08T08:48:56.857Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
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              "version": "6.6.140",
              "versionType": "semver"
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              "version": "7.0.4",
              "versionType": "semver"
            },
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              "version": "7.1",
              "versionType": "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.

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.

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EUVD-2026-364804

CVE-2026-43499 (GCVE-0-2026-43499)

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Nomenclature

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