{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.180-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.96-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.1.4-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux-6.12"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.100-1~deb12u1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "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-\u003eip_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:  \u003cIRQ\u003e  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  \u003c/IRQ\u003e  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",
  "id": "DEBIAN-CVE-2026-64423",
  "modified": "2026-09-09T08:47:35.501907585Z",
  "published": "2026-07-25T10:17:26.350Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-64423"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-64423"
  ]
}