Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — net: rose: fix timer races against user threads
AV AC PR UI S C I A CVSS EPSS %ile KEV
L H L N U H H H 7.0 .0016 6.0 —
AFFECTED
Product Versions Fixed
Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – —
Linux 2.6.12 – 5.4.291
TIMELINE
Dec 29 Reserved by Linux
Feb 27 Published (CNA: Linux)
Jul 30 RESCORED — CVE-2025-21718 (Linux). CVSS 7.8 → 7 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
net: rose: fix timer races against user threads
Rose timers only acquire the socket spinlock, without
checking if the socket is owned by one user thread.
Add a check and rearm the timers if needed.
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x31d/0x360 net/rose/rose_timer.c:174
Read of size 2 at addr ffff88802f09b82a by task swapper/0/0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc5-syzkaller-00172-gd1bf27c4e176 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x169/0x550 mm/kasan/report.c:489
kasan_report+0x143/0x180 mm/kasan/report.c:602
rose_timer_expiry+0x31d/0x360 net/rose/rose_timer.c:174
call_timer_fn+0x187/0x650 kernel/time/timer.c:1793
expire_timers kernel/time/timer.c:1844 [inline]
__run_timers kernel/time/timer.c:2418 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2430
run_timer_base kernel/time/timer.c:2439 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449
handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
__do_softirq kernel/softirq.c:595 [inline]
invoke_softirq kernel/softirq.c:435 [inline]
__irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
</IRQ>
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| December 29, 2024 | Reserved | Reserved by Linux |
| February 27, 2025 | Published | Published (CNA: Linux) |
| July 30, 2026 | RESCORED | RESCORED — CVE-2025-21718 (Linux). CVSS 7.8 → 7 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | — |
| Linux | Linux | — | 2.6.12 | 5.4.291 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2025-21718 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.