{"id":"CVE-2026-43139","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-43139","generatedAt":"2026-10-28T00:20:05.173Z","title":"In the Linux kernel, the following vulnerability has been resolved: xfrm6: fix uninitialized saddr in xfrm6_get_saddr() xfrm6_get_saddr() does not check the return value of ipv6_dev_get_saddr().","description":"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->in6 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.","published":"2026-05-06T12:16:31.000Z","lastModified":"2026-10-19T20:18:08.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H"},"cwe":["CWE-908","CWE-457"],"affected":["linux/linux kernel"],"epss":{"score":0.00375,"percentile":0.31208,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/1799d8abeabc68ec05679292aaf6cba93b343c05","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3dcd1664ac15eee6a690daec7c4ffc59190406f7","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4f28141786e1fe884ce42a5197ba9beed540f0ea","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6535867673bf301d52aa00593a4d1d18cc3922fa","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/719918fc88df6da023dfff370cd965151a5afd7f","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c7221e7bd8fc2ef38a0b27be580d9d202281306b","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dc0abce055134cb83b0d981d31ceb20dda419787","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/eb2ee15290af14c60b45cf2b73f5687d1d077d9b","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43139","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}