CVE-2026-64218

Published Jul 24, 2026

Last updated 2 months ago

CVSS high 7.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: batman-adv: bla: fix report_work leak on backbone_gw purge batadv_bla_purge_backbone_gw() removes stale backbone gateway entries, but fails to properly handle their associated report_work: - If report_work is running, the purge must wait for it to finish before freeing the backbone_gw, otherwise the worker may access freed memory (e.g. bat_priv). - If report_work is pending, the purge must cancel it and release the reference held for that pending work item. The previous implementation called hlist_for_each_entry_safe() inside a spin_lock_bh() section, but cancel_work_sync() may sleep and therefore cannot be called from within a spinlock-protected region. Restructure the loop to handle one entry per spinlock critical section: acquire the lock, find the next entry to purge, remove it from the hash list, then release the lock before calling cancel_work_sync() and dropping the hash_entry reference. Repeat until no more entries require purging.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

  1. There is a new vulnerability with elevated criticality in Linux Kernel (CVE-2026-64218) https://t.co/gdZJB868Ww

    @vuldb

    24 Jul 2026

    100 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.