ipv4: igmp: remove multicast group from hash table on device destruction
In the Linux kernel, the following vulnerability has been resolved: ipv4: igmp: remove multicast group from hash table on device destruction When a device is destroyed under RTNL, ip_mc_destroy_dev() iterates through the multicast list and calls ip_ma_put() on each membership, scheduling them for RCU reclamation. However, they are not unlinked from the device's multicast hash table (mc_hash). Since the device remains published in dev->ip_ptr until after ip_mc_destroy_dev() completes, concurrent RCU readers traversing mc_hash can still locate and access the multicast group after its refcount is decremented. If the RCU callback runs and frees the group while a reader is accessing it, a use-after-free occurs. Fix this by unlinking the multicast group from mc_hash using ip_mc_hash_remove() before scheduling it for reclamation. BUG: KASAN: slab-use-after-free in ip_check_mc_rcu+0x149/0x3f0 Read of size 4 at addr ffff888009bf1408 by task mausezahn/2276 Call Trace: dump_stack_lvl+0x67/0x90 print_report+0x175/0x7c0 kasan_report+0x147/0x180 ip_check_mc_rcu+0x149/0x3f0 udp_v4_early_demux+0x36d/0x12d0 ip_rcv_finish_core+0xb8b/0x1390 ip_rcv_finish+0x54/0x120 NF_HOOK+0x213/0x2b0 __netif_receive_skb+0x126/0x340 process_backlog+0x4f2/0xf00 __napi_poll+0x92/0x2c0 net_rx_action+0x583/0xc60 handle_softirqs+0x236/0x7f0 do_softirq+0x57/0x80 Allocated by task 2239: kasan_save_track+0x3e/0x80 __kasan_kmalloc+0x72/0x90 ____ip_mc_inc_group+0x31a/0xa40 __ip_mc_join_group+0x334/0x3f0 do_ip_setsockopt+
CVE-2026-64423
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-64423
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "412ba7def06ffe974ba9a1d862b022362c54ffa5",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "c6cb5f8ebe1c1a78710c19f102db9fe48b9e6ba9",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "5f42729d74bd6c61306d864423290d92962de4e1",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "76d030ac95e17f91d69a595f17ebc5979700cf9a",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "8820b530cb2388503d7418228d03ba074bf7a03e",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "2ca18df1c2611f70eb3eb487e02ae85eb703b284",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "f91883031e5a62877a29ce139442973cbea769f1",
"versionType": "git"
},
{
"status": "affected",
"version": "e9897071350bd9d94a56b5b6f79c85b1a98fc7e7",
"lessThan": "7993211bde166471dffac074dc965489f86531f8",
"versionType": "git"
}
],
"programFiles": [
"net/ipv4/igmp.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.11"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.11",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.96",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.4",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/ipv4/igmp.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-64423
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #41040 · Revision 1
- Added to Heist Feed
- Publisher date