CVE-2025-39773
EUVD-2025-2893911.09.2025, 17:15
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.EnginsightAffected Products (NVD)
| Vendor | Product | Version |
|---|---|---|
| linux | linux_kernel | 2.6.34 ≤ 𝑥 < 5.15.190 |
| linux | linux_kernel | 5.16 ≤ 𝑥 < 6.1.149 |
| linux | linux_kernel | 6.2 ≤ 𝑥 < 6.6.103 |
| linux | linux_kernel | 6.7 ≤ 𝑥 < 6.12.44 |
| linux | linux_kernel | 6.13 ≤ 𝑥 < 6.16.4 |
| linux | linux_kernel | 6.17:rc1 |
| linux | linux_kernel | 6.17:rc2 |
| debian | debian_linux | 11.0 |
𝑥
= Vulnerable software versions
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
| Vendor | Product | Version | Source |
|---|---|---|---|
| Siemens | SIMATIC CN 4100 | 𝑥 < V5.0 | ADP |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN\/DP MFP | V3.1.5 ≤ 𝑥 < * | ADP |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN\/DP MFP | V3.1.5 ≤ 𝑥 < * | ADP |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN\/DP MFP | V3.1.5 ≤ 𝑥 < * | ADP |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN\/DP MFP | V3.1.5 ≤ 𝑥 < * | ADP |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN\/DP MFP | V3.1.5 ≤ 𝑥 < * | ADP |
| siemens | simatic_cn_4100 | 𝑥 < 5.0 | ADP |
Debian Releases
openSUSE / SLES Releases
openSUSE Product | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| cluster-md-kmp-default |
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| dlm-kmp-default |
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| gfs2-kmp-default |
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| kernel-64kb |
| ||||||||||||||
| kernel-azure |
| ||||||||||||||
| kernel-default |
| ||||||||||||||
| kernel-default-base |
| ||||||||||||||
| kernel-default-man |
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| kernel-docs |
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| kernel-macros |
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| kernel-obs-build |
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| kernel-source |
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| kernel-source-azure |
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| kernel-syms |
| ||||||||||||||
| kernel-syms-azure |
| ||||||||||||||
| kernel-zfcpdump |
| ||||||||||||||
| ocfs2-kmp-default |
|
Common Weakness Enumeration
References