{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf"
            },
            {
              "fixed": "c0f973bb5118dd1b146cda3fcc8af6f6057befec"
            },
            {
              "fixed": "3b539b317cd052236fed0350364ff1268996ba46"
            },
            {
              "fixed": "db9d8e3b670f841755bc2018f178472dc6064d27"
            },
            {
              "fixed": "31efa656cf6aface26e88f038c14f22ee6ca1500"
            },
            {
              "fixed": "291accf36febce751021888de5f15090f4875b56"
            },
            {
              "fixed": "ca33df36aa0143a1d04f57d2086020c12e7eddb7"
            },
            {
              "fixed": "163847552a571bd55094291f4ffcdc1de0f14a7b"
            },
            {
              "fixed": "beb33f8ee1ca83acddb2a5ae80f3d22ec550b4c3"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.2.0"
            },
            {
              "fixed": "5.10.265"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.216"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.183"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.152"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.104"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.45"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74586.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: clear new_transport when removing a peer\n\nsctp_process_asconf_param() stores a newly added peer transport in\nasoc-\u003enew_transport. After all parameters in the ASCONF chunk have been\nprocessed, sctp_sf_do_asconf() uses this pointer to send a HEARTBEAT to the\nnew transport.\n\nAn authenticated ASCONF from a remote SCTP peer can add a transport and\nremove it again with a wildcard DEL-IP parameter in the same chunk. The\nwildcard deletion preserves the transport on which the ASCONF arrived, but\nremoves the newly added transport through\nsctp_assoc_del_nonprimary_peers(). The removal does not clear\nasoc-\u003enew_transport, leaving it pointing to the removed transport.\n\nsctp_sf_do_asconf() then creates a HEARTBEAT whose chunk-\u003etransport points\nto the removed transport without holding a transport reference. During\nlocal address replacement, src_out_of_asoc_ok keeps this HEARTBEAT on\ncontrol_chunk_list. After the transport is freed by RCU, a successful\nASCONF_ACK for the replacement address releases the queued HEARTBEAT and\nsctp_outq_select_transport() reads the freed transport's state.\n\nThe issue was found during a static audit of SCTP objects. With an\nauthenticated peer, the reproducer triggered the same KASAN report in 2\nof 2 unpatched runs on a KASAN-enabled netdev/main kernel:\n\n  BUG: KASAN: slab-use-after-free in sctp_outq_select_transport\n  Read of size 4 at addr ffff88800b9bd95c by task python3/197\n\n  Call Trace:\n   sctp_outq_select_transport+0x549/0x8b0 [sctp]\n   sctp_outq_flush+0x306/0x2c60 [sctp]\n   sctp_transport_immediate_rtx+0xaf/0x260 [sctp]\n   sctp_process_asconf_ack+0xa48/0xf70 [sctp]\n\n  Allocated by task 197:\n   sctp_transport_new+0x68/0x650 [sctp]\n   sctp_assoc_add_peer+0x258/0x12a0 [sctp]\n   sctp_process_asconf+0x5e9/0x1090 [sctp]\n\n  Last potentially related work creation:\n   __call_rcu_common.constprop.0+0x77/0xb70\n   sctp_assoc_del_nonprimary_peers+0x7c/0xd0 [sctp]\n   sctp_process_asconf+0xd9c/0x1090 [sctp]\n\nThe first invalid access was a four-byte read of transport-\u003estate at\nnet/sctp/outqueue.c:833. The same reproducer completed the full\nauthenticated ASCONF and local-address replacement sequence with this\nchange without a KASAN report or oops.\n\nClear new_transport when its peer is removed, before it can be used to\ncreate the HEARTBEAT.",
  "id": "CVE-2026-74586",
  "modified": "2026-08-27T11:30:53.722417002Z",
  "published": "2026-08-22T15:31:39.094Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/163847552a571bd55094291f4ffcdc1de0f14a7b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/291accf36febce751021888de5f15090f4875b56"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/31efa656cf6aface26e88f038c14f22ee6ca1500"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3b539b317cd052236fed0350364ff1268996ba46"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/beb33f8ee1ca83acddb2a5ae80f3d22ec550b4c3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c0f973bb5118dd1b146cda3fcc8af6f6057befec"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ca33df36aa0143a1d04f57d2086020c12e7eddb7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/db9d8e3b670f841755bc2018f178472dc6064d27"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74586.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74586"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "sctp: clear new_transport when removing a peer"
}