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 — ipv6: mcast: fix data-race in ipv6_mc_down / mld_ifc_work
AV AC PR UI S C I A CVSS EPSS %ile KEV
L H L N U N N H 4.7 .0019 8.6 —
AFFECTED
Product Versions Fixed
Linux 07a7a183f22cf1e3ce5ed336fe62a6248a2f6738 – —
Linux 5.13 – 5.15.148
TIMELINE
Feb 19 Reserved by Linux
Mar 18 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2024-26631 (Linux). CVSS 7.8 → 4.7 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: fix data-race in ipv6_mc_down / mld_ifc_work
idev->mc_ifc_count can be written over without proper locking.
Originally found by syzbot [1], fix this issue by encapsulating calls
to mld_ifc_stop_work() (and mld_gq_stop_work() for good measure) with
mutex_lock() and mutex_unlock() accordingly as these functions
should only be called with mc_lock per their declarations.
[1]
BUG: KCSAN: data-race in ipv6_mc_down / mld_ifc_work
write to 0xffff88813a80c832 of 1 bytes by task 3771 on cpu 0:
mld_ifc_stop_work net/ipv6/mcast.c:1080 [inline]
ipv6_mc_down+0x10a/0x280 net/ipv6/mcast.c:2725
addrconf_ifdown+0xe32/0xf10 net/ipv6/addrconf.c:3949
addrconf_notify+0x310/0x980
notifier_call_chain kernel/notifier.c:93 [inline]
raw_notifier_call_chain+0x6b/0x1c0 kernel/notifier.c:461
__dev_notify_flags+0x205/0x3d0
dev_change_flags+0xab/0xd0 net/core/dev.c:8685
do_setlink+0x9f6/0x2430 net/core/rtnetlink.c:2916
rtnl_group_changelink net/core/rtnetlink.c:3458 [inline]
__rtnl_newlink net/core/rtnetlink.c:3717 [inline]
rtnl_newlink+0xbb3/0x1670 net/core/rtnetlink.c:3754
rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6558
netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6576
netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
netlink_unicast+0x589/0x650 net/netlink/af_netlink.c:1368
netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1910
...
write to 0xffff88813a80c832 of 1 bytes by task 22 on cpu 1:
mld_ifc_work+0x54c/0x7b0 net/ipv6/mcast.c:2653
process_one_work kernel/workqueue.c:2627 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700
worker_thread+0x525/0x730 kernel/workqueue.c:2781
...
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| February 19, 2024 | Reserved | Reserved by Linux |
| March 18, 2024 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2024-26631 (Linux). CVSS 7.8 → 4.7 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 07a7a183f22cf1e3ce5ed336fe62a6248a2f6738 | — |
| Linux | Linux | — | 5.13 | 5.15.148 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2024-26631 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.