CVE Catalog

CVE-2026-64093

HighCVSS 8.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.34%

26th percentile - higher than 26% of all known CVEs

Summary

In the Linux kernel, the batman-adv (tp_meter) module had a vulnerability where batadv_tp_sender_cleanup() used an unsafe combination of timer_delete_sync() and timer_delete() to stop a timer. This could lead to the timer being re-armed after cleanup, causing a use-after-free condition.

Risk Assessment

The risk is a potential use-after-free bug in the kernel, which could lead to system crashes, information leaks, or potentially privilege escalation by a local attacker.

Recommendation

Immediately update the Linux kernel to a version containing the fix that replaces the timer_delete_sync() and timer_delete() calls with a single timer_shutdown_sync().

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: batman-adv: tp_meter: directly shut down timer on cleanup batadv_tp_sender_cleanup() was calling timer_delete_sync() followed by timer_delete() to guard against the timer handler re-arming itself between the two calls. This double-deletion hack relied on the sending status being set to 0 to suppress re-arming. Replace both calls with a single timer_shutdown_sync(). This function both waits for any running timer callback to complete (like timer_delete_sync()) and permanently disarms the timer so it cannot be re-armed afterwards, making re-arming prevention unconditional and self-documenting. The re-arming property is also required because otherwise: 1. context 0 (batadv_tp_recv_ack()) checks in batadv_tp_reset_sender_timer() if sending is still 1 -> it is 2. context 1 changes in batadv_tp_sender_shutdown() sending to 0 and in this process forces the kthread to stop timer in batadv_tp_sender_cleanup() 3. context 0 continues in batadv_tp_reset_sender_timer() and rearms the timer -> but the reference for it is already gone

Vulnerability data from NVD (NIST) · CISA KEV · EPSS