In the Linux kernel, the following vulnerability has been resolved:
net: bridge: fix soft lockup in br_multicast_query_expired()
When set multicast_query_interval to a large value, the local variable
'time' in br_multicast_send_query() may overflow. If the time is smaller
than jiffies, the timer will expire immediately, and then call mod_timer()
again, which creates a loop and may trigger the following soft lockup
issue.
watchdog: BUG: soft lockup - CPU#1 stuck for 221s! [rb_consumer:66]
CPU: 1 UID: 0 PID: 66 Comm: rb_consumer Not tainted 6.16.0+ #259 PREEMPT(none)
Call Trace:
<IRQ>
__netdev_alloc_skb+0x2e/0x3a0
br_ip6_multicast_alloc_query+0x212/0x1b70
__br_multicast_send_query+0x376/0xac0
br_multicast_send_query+0x299/0x510
br_multicast_query_expired.constprop.0+0x16d/0x1b0
call_timer_fn+0x3b/0x2a0
__run_timers+0x619/0x950
run_timer_softirq+0x11c/0x220
handle_softirqs+0x18e/0x560
__irq_exit_rcu+0x158/0x1a0
sysvec_apic_timer_interrupt+0x76/0x90
</IRQ>
This issue can be reproduced with:
ip link add br0 type bridge
echo 1 > /sys/class/net/br0/bridge/multicast_querier
echo 0xffffffffffffffff >
/sys/class/net/br0/bridge/multicast_query_interval
ip link set dev br0 up
The multicast_startup_query_interval can also cause this issue. Similar to
the commit 99b40610956a ("net: bridge: mcast: add and enforce query
interval minimum"), add check for the query interval maximum to fix this
issue.
References
Configurations
Configuration 1 (hide)
|
Configuration 2 (hide)
|
History
16 Jan 2026, 20:11
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Linux
Debian Debian debian Linux Linux linux Kernel |
|
| CPE | cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
|
| CWE | CWE-667 | |
| References | () https://git.kernel.org/stable/c/34171b9e53bd1dc264f5556579f2b04f04435c73 - Patch | |
| References | () https://git.kernel.org/stable/c/43e281fde5e76a866a4d10780c35023f16c0e432 - Patch | |
| References | () https://git.kernel.org/stable/c/5bf5fce8a0c2a70d063af778fdb5b27238174cdd - Patch | |
| References | () https://git.kernel.org/stable/c/96476b043efb86a94f2badd260f7f99c97bd5893 - Patch | |
| References | () https://git.kernel.org/stable/c/bdb19cd0de739870bb3494c815138b9dc30875c4 - Patch | |
| References | () https://git.kernel.org/stable/c/d1547bf460baec718b3398365f8de33d25c5f36f - Patch | |
| References | () https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html - Third Party Advisory | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
03 Nov 2025, 18:16
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
11 Sep 2025, 17:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2025-09-11 17:15
Updated : 2026-01-16 20:11
NVD link : CVE-2025-39773
Mitre link : CVE-2025-39773
CVE.ORG link : CVE-2025-39773
JSON object : View
Products Affected
debian
- debian_linux
linux
- linux_kernel
CWE
CWE-667
Improper Locking
