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EUVD-2026-356627

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 08:28

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": "2026-10-02T08:28:45.591833+00:00",
  "id": "EUVD-2026-356627"
}

CVE-2026-31703 (GCVE-0-2026-31703)

Vulnerability from cvelistv5 – Published: 2026-05-01 13:56 – Updated: 2026-08-20 12:32

Title

writeback: Fix use after free in inode_switch_wbs_work_fn()

Summary

In the Linux kernel, the following vulnerability has been resolved: writeback: Fix use after free in inode_switch_wbs_work_fn() inode_switch_wbs_work_fn() has a loop like: wb_get(new_wb); while (1) { list = llist_del_all(&new_wb->switch_wbs_ctxs); /* Nothing to do? */ if (!list) break; ... process the items ... } Now adding of items to the list looks like: wb_queue_isw() if (llist_add(&isw->list, &wb->switch_wbs_ctxs)) queue_work(isw_wq, &wb->switch_work); Because inode_switch_wbs_work_fn() loops when processing isw items, it can happen that wb->switch_work is pending while wb->switch_wbs_ctxs is empty. This is a problem because in that case wb can get freed (no isw items -> no wb reference) while the work is still pending causing use-after-free issues. We cannot just fix this by cancelling work when freeing wb because that could still trigger problematic 0 -> 1 transitions on wb refcount due to wb_get() in inode_switch_wbs_work_fn(). It could be all handled with more careful code but that seems unnecessarily complex so let's avoid that until it is proven that the looping actually brings practical benefit. Just remove the loop from inode_switch_wbs_work_fn() instead. That way when wb_queue_isw() queues work, we are guaranteed we have added the first item to wb->switch_wbs_ctxs and nobody is going to remove it (and drop the wb reference it holds) until the queued work runs.

Severity

7.8 (High)


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

7 (High)


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

CWE

CWE-825 - Expired Pointer Dereference

Assigner

Linux mitre root Scorecard

References

9 references

URL	Tags
https://git.kernel.org/stable/c/382cf81cae89e58d2…
https://git.kernel.org/stable/c/19ec404b079be057b…
https://git.kernel.org/stable/c/156cc63691c1f2090…
https://git.kernel.org/stable/c/028103656b84273c7…
https://git.kernel.org/stable/c/9223e5f30403a9b50…
https://git.kernel.org/stable/c/6689f01d6740cf358…
https://access.redhat.com/security/cve/CVE-2026-31703	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2464385	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex

Impacted products

7 products

Vendor	Product	Version
Linux	Linux	Affected: d072b38a64ddbc2d58c2e525a24af24ecbfebcb7 , < 382cf81cae89e58d22b4bdc38891cd4d0b9ba921 (git) Affected: ac7b2c21f2269d815ad0cdf0f8258d55185b805c , < 19ec404b079be057b387643ba0c69bbcc5867c35 (git) Affected: fabfc1fcddc5d8185722d4fde5f0968c4760b71e , < 156cc63691c1f20905510b1007896e090355e6c2 (git) Affected: e1b849cfa6b61f1c866a908c9e8dd9b5aaab820b , < 028103656b84273c73e9e271cf95c9f3421f4b8a (git) Affected: e1b849cfa6b61f1c866a908c9e8dd9b5aaab820b , < 9223e5f30403a9b506d6d0bff4f2e29a2d7d46af (git) Affected: e1b849cfa6b61f1c866a908c9e8dd9b5aaab820b , < 6689f01d6740cf358932b3e97ee968c6099800d9 (git)
Linux	Linux	Affected: 6.18 Unaffected: 0 , < 6.18 (semver) Unaffected: 6.18.25 , ≤ 6.18.* (semver) Unaffected: 7.0.2 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix)
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Show details on NVD website

JSON

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{
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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.
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EUVD-2026-356627

CVE-2026-31703 (GCVE-0-2026-31703)

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Nomenclature

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