{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "4ab9e64e5e3c0516577818804aaf13a630d67bc9"
            },
            {
              "fixed": "faa6ea32797a1847790514ff0da1be1d09771580"
            },
            {
              "fixed": "82baeb871e8f04906bc886273fdf0209e1754eb3"
            },
            {
              "fixed": "6e5e3c87b7e6212f1d8414fc2e4d158b01e12025"
            },
            {
              "fixed": "fe463e76c9b4b0b43b5ee8961b4c500231f1a3f6"
            },
            {
              "fixed": "7edca70751b9bdb5b83eed53cde21eccf3c86147"
            },
            {
              "fixed": "01f34a80ac23ae90b1909b94b4ed05343a62f646"
            },
            {
              "fixed": "52fdda318ef2362fc5936385bcb8b3d0328ee629"
            },
            {
              "fixed": "6a2b724460cb67caed500c508c2ae5cf012e4db4"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.26"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.131"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.80"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.21"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31427.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_sip: fix use of uninitialized rtp_addr in process_sdp\n\nprocess_sdp() declares union nf_inet_addr rtp_addr on the stack and\npasses it to the nf_nat_sip sdp_session hook after walking the SDP\nmedia descriptions. However rtp_addr is only initialized inside the\nmedia loop when a recognized media type with a non-zero port is found.\n\nIf the SDP body contains no m= lines, only inactive media sections\n(m=audio 0 ...) or only unrecognized media types, rtp_addr is never\nassigned. Despite that, the function still calls hooks-\u003esdp_session()\nwith \u0026rtp_addr, causing nf_nat_sdp_session() to format the stale stack\nvalue as an IP address and rewrite the SDP session owner and connection\nlines with it.\n\nWith CONFIG_INIT_STACK_ALL_ZERO (default on most distributions) this\nresults in the session-level o= and c= addresses being rewritten to\n0.0.0.0 for inactive SDP sessions. Without stack auto-init the\nrewritten address is whatever happened to be on the stack.\n\nFix this by pre-initializing rtp_addr from the session-level connection\naddress (caddr) when available, and tracking via a have_rtp_addr flag\nwhether any valid address was established. Skip the sdp_session hook\nentirely when no valid address exists.",
  "id": "CVE-2026-31427",
  "modified": "2026-07-08T05:37:57.450897960Z",
  "published": "2026-04-13T13:40:30.280Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/01f34a80ac23ae90b1909b94b4ed05343a62f646"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/52fdda318ef2362fc5936385bcb8b3d0328ee629"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6a2b724460cb67caed500c508c2ae5cf012e4db4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6e5e3c87b7e6212f1d8414fc2e4d158b01e12025"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7edca70751b9bdb5b83eed53cde21eccf3c86147"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/82baeb871e8f04906bc886273fdf0209e1754eb3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/faa6ea32797a1847790514ff0da1be1d09771580"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fe463e76c9b4b0b43b5ee8961b4c500231f1a3f6"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31427.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31427"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "netfilter: nf_conntrack_sip: fix use of uninitialized rtp_addr in process_sdp"
}