CVE-2026-64423ipv4: igmp: remove multicast group from hash table on device destruction
- 7.8HighCVSS base score
- 0.13%Exploitation in 30 daysEPSS · top 97% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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: <IRQ> 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 </IRQ> 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+0x16fa/0x2010 ip_setsockopt+0x3f/0x90 do_sock_setsockopt+0x1ad/0x300 Freed by task 0: kasan_save_track+0x3e/0x80 kasan_save_free_info+0x40/0x50 __kasan_slab_free+0x3a/0x60 __rcu_free_sheaf_prepare+0xd4/0x220 rcu_free_sheaf+0x36/0x190 rcu_core+0x8d9/0x12f0 handle_softirqs+0x236/0x7f0
Timeline
ID reserved
By Linux
- 6 days later
· 6 days later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.13% · top 97% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < 412ba7def06ffe974ba9a1d862b022362c54ffa5
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < c6cb5f8ebe1c1a78710c19f102db9fe48b9e6ba9
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < 5f42729d74bd6c61306d864423290d92962de4e1
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < 76d030ac95e17f91d69a595f17ebc5979700cf9a
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < 8820b530cb2388503d7418228d03ba074bf7a03e
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < 2ca18df1c2611f70eb3eb487e02ae85eb703b284
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < f91883031e5a62877a29ce139442973cbea769f1
- affected e9897071350bd9d94a56b5b6f79c85b1a98fc7e7 – < 7993211bde166471dffac074dc965489f86531f8
- affected 3.11
- unaffected < 3.11
- unaffected 5.10.261 – ≤ 5.10.*
- unaffected 5.15.212 – ≤ 5.15.*
- unaffected 6.1.178 – ≤ 6.1.*
- unaffected 6.6.145 – ≤ 6.6.*
- unaffected 6.12.96 – ≤ 6.12.*
- unaffected 6.18.39 – ≤ 6.18.*
- unaffected 7.1.4 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References10
- https://git.kernel.org/stable/c/412ba7def06ffe974ba9a1d862b022362c54ffa5 (opens in a new tab)
- https://git.kernel.org/stable/c/c6cb5f8ebe1c1a78710c19f102db9fe48b9e6ba9 (opens in a new tab)
- https://git.kernel.org/stable/c/5f42729d74bd6c61306d864423290d92962de4e1 (opens in a new tab)
- https://git.kernel.org/stable/c/76d030ac95e17f91d69a595f17ebc5979700cf9a (opens in a new tab)
- https://git.kernel.org/stable/c/8820b530cb2388503d7418228d03ba074bf7a03e (opens in a new tab)
- https://git.kernel.org/stable/c/2ca18df1c2611f70eb3eb487e02ae85eb703b284 (opens in a new tab)
- https://git.kernel.org/stable/c/f91883031e5a62877a29ce139442973cbea769f1 (opens in a new tab)
- https://git.kernel.org/stable/c/7993211bde166471dffac074dc965489f86531f8 (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-48967 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://cveledger.app/cve/CVE-2026-64423)Record last updated .