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EUVD-2026-336340

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:51

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": "2026-10-02T07:51:55.292315+00:00",
  "id": "EUVD-2026-336340"
}

CVE-2025-38457 (GCVE-0-2025-38457)

Vulnerability from cvelistv5 – Published: 2025-07-25 15:27 – Updated: 2026-07-14 12:42

Title

net/sched: Abort __tc_modify_qdisc if parent class does not exist

Summary

In the Linux kernel, the following vulnerability has been resolved: net/sched: Abort __tc_modify_qdisc if parent class does not exist Lion's patch [1] revealed an ancient bug in the qdisc API. Whenever a user creates/modifies a qdisc specifying as a parent another qdisc, the qdisc API will, during grafting, detect that the user is not trying to attach to a class and reject. However grafting is performed after qdisc_create (and thus the qdiscs' init callback) is executed. In qdiscs that eventually call qdisc_tree_reduce_backlog during init or change (such as fq, hhf, choke, etc), an issue arises. For example, executing the following commands: sudo tc qdisc add dev lo root handle a: htb default 2 sudo tc qdisc add dev lo parent a: handle beef fq Qdiscs such as fq, hhf, choke, etc unconditionally invoke qdisc_tree_reduce_backlog() in their control path init() or change() which then causes a failure to find the child class; however, that does not stop the unconditional invocation of the assumed child qdisc's qlen_notify with a null class. All these qdiscs make the assumption that class is non-null. The solution is ensure that qdisc_leaf() which looks up the parent class, and is invoked prior to qdisc_create(), should return failure on not finding the class. In this patch, we leverage qdisc_leaf to return ERR_PTRs whenever the parentid doesn't correspond to a class, so that we can detect it earlier on and abort before qdisc_create is called. [1] https://lore.kernel.org/netdev/d912cbd7-193b-4269-9857-525bee8bbb6a@gmail.com/

Severity

No CVSS data available.

Assigner

Linux mitre root Scorecard

References

11 references

URL	Tags
https://git.kernel.org/stable/c/923a276c74e25073a…
https://git.kernel.org/stable/c/90436e72c9622c2f7…
https://git.kernel.org/stable/c/25452638f133ac19d…
https://git.kernel.org/stable/c/23c165dde88eac405…
https://git.kernel.org/stable/c/4c691d1b6b6dbd73f…
https://git.kernel.org/stable/c/8ecd651ef24ab5012…
https://git.kernel.org/stable/c/e28a383d6485c3bb5…
https://git.kernel.org/stable/c/ffdde7bf5a439aaa1…
https://lists.debian.org/debian-lts-announce/2025…
https://lists.debian.org/debian-lts-announce/2025…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

5 products

Vendor	Product	Version
Linux	Linux	Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < 923a276c74e25073ae391e930792ac86a9f77f1e (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < 90436e72c9622c2f70389070088325a3232d339f (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < 25452638f133ac19d75af3f928327d8016952c8e (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < 23c165dde88eac405eebb59051ea1fe139a45803 (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < 4c691d1b6b6dbd73f30ed9ee7da05f037b0c49af (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < 8ecd651ef24ab50123692a4e3e25db93cb11602a (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < e28a383d6485c3bb51dc5953552f76c4dea33eea (git) Affected: 5e50da01d0ce7ef0ba3ed6cfabd62f327da0aca6 , < ffdde7bf5a439aaa1955ebd581f5c64ab1533963 (git)
Linux	Linux	Affected: 2.6.20 Unaffected: 0 , < 2.6.20 (semver) Unaffected: 5.4.296 , ≤ 5.4.* (semver) Unaffected: 5.10.240 , ≤ 5.10.* (semver) Unaffected: 5.15.189 , ≤ 5.15.* (semver) Unaffected: 6.1.146 , ≤ 6.1.* (semver) Unaffected: 6.6.99 , ≤ 6.6.* (semver) Unaffected: 6.12.39 , ≤ 6.12.* (semver) Unaffected: 6.15.7 , ≤ 6.15.* (semver) Unaffected: 6.16 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)

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Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
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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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EUVD-2026-336340

CVE-2025-38457 (GCVE-0-2025-38457)

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