{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a1e59abf824969554b90facd44a4ab16e265afa4"
            },
            {
              "fixed": "4f28141786e1fe884ce42a5197ba9beed540f0ea"
            },
            {
              "fixed": "6535867673bf301d52aa00593a4d1d18cc3922fa"
            },
            {
              "fixed": "eb2ee15290af14c60b45cf2b73f5687d1d077d9b"
            },
            {
              "fixed": "719918fc88df6da023dfff370cd965151a5afd7f"
            },
            {
              "fixed": "dc0abce055134cb83b0d981d31ceb20dda419787"
            },
            {
              "fixed": "c7221e7bd8fc2ef38a0b27be580d9d202281306b"
            },
            {
              "fixed": "3dcd1664ac15eee6a690daec7c4ffc59190406f7"
            },
            {
              "fixed": "1799d8abeabc68ec05679292aaf6cba93b343c05"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.19"
            },
            {
              "fixed": "5.10.252"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.202"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.165"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.128"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.75"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.16"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43139.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm6: fix uninitialized saddr in xfrm6_get_saddr()\n\nxfrm6_get_saddr() does not check the return value of\nipv6_dev_get_saddr(). When ipv6_dev_get_saddr() fails to find a suitable\nsource address (returns -EADDRNOTAVAIL), saddr-\u003ein6 is left\nuninitialized, but xfrm6_get_saddr() still returns 0 (success).\n\nThis causes the caller xfrm_tmpl_resolve_one() to use the uninitialized\naddress in xfrm_state_find(), triggering KMSAN warning:\n\n=====================================================\nBUG: KMSAN: uninit-value in xfrm_state_find+0x2424/0xa940\n xfrm_state_find+0x2424/0xa940\n xfrm_resolve_and_create_bundle+0x906/0x5a20\n xfrm_lookup_with_ifid+0xcc0/0x3770\n xfrm_lookup_route+0x63/0x2b0\n ip_route_output_flow+0x1ce/0x270\n udp_sendmsg+0x2ce1/0x3400\n inet_sendmsg+0x1ef/0x2a0\n __sock_sendmsg+0x278/0x3d0\n __sys_sendto+0x593/0x720\n __x64_sys_sendto+0x130/0x200\n x64_sys_call+0x332b/0x3e70\n do_syscall_64+0xd3/0xf80\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nLocal variable tmp.i.i created at:\n xfrm_resolve_and_create_bundle+0x3e3/0x5a20\n xfrm_lookup_with_ifid+0xcc0/0x3770\n=====================================================\n\nFix by checking the return value of ipv6_dev_get_saddr() and propagating\nthe error.",
  "id": "CVE-2026-43139",
  "modified": "2026-07-08T05:38:38.110313165Z",
  "published": "2026-05-06T11:27:24.898Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1799d8abeabc68ec05679292aaf6cba93b343c05"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3dcd1664ac15eee6a690daec7c4ffc59190406f7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4f28141786e1fe884ce42a5197ba9beed540f0ea"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6535867673bf301d52aa00593a4d1d18cc3922fa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/719918fc88df6da023dfff370cd965151a5afd7f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c7221e7bd8fc2ef38a0b27be580d9d202281306b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/dc0abce055134cb83b0d981d31ceb20dda419787"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eb2ee15290af14c60b45cf2b73f5687d1d077d9b"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43139.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43139"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "xfrm6: fix uninitialized saddr in xfrm6_get_saddr()"
}