CVE WatchJul 8, 2026

CVE-2026-52919

In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix tp_meter counter underflow during shutdown batadv_tp_s

CVSS

7.8

High

EPSS

0.1%

KEV

—

Exploit Today

0-100

Published: Jun 24, 2026 · Last modified: Jul 8, 2026 · CWE-191

EPSS · 30d

0.1%EPSS · 30 days0.1%

2026-06-302026-07-16

Technical description

In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix tp_meter counter underflow during shutdown batadv_tp_sender_shutdown() unconditionally decrements the "sending" atomic counter. If multiple paths (e.g. timeout, user cancel, and normal finish) call this function, the counter can underflow to -1. Since the sender logic treats any non-zero value as "still sending", a negative value causes the sender kthread to loop indefinitely. This leads to a use-after-free when the interface is removed while the zombie thread is still active. Fix this by using atomic_xchg() to ensure the counter only transitions from 1 to 0 once. [sven: added missing change in batadv_tp_send]

Official references

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