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    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-31427",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-03-09T15:48:24.088Z",
        "datePublished": "2026-04-13T13:40:30.280Z",
        "dateUpdated": "2026-07-14T12:47:45.337Z"
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                "dateUpdated": "2026-05-11T22:08:29.865Z"
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                {
                    "lang": "en",
                    "value": "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->sdp_session()\nwith &rtp_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."
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                            "status": "unaffected",
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                            "status": "unaffected",
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