{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-23439", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-23439", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-04-03T15:15:23.734Z", "updatedAt": "2026-10-15T01:15:01.223Z", "importedAt": "2026-10-24T01:58:02.025Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "udp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nudp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n\n\nWhen CONFIG_IPV6 is disabled, the udp_sock_create6() function returns 0\n(success) without actually creating a socket. Callers such as\nfou_create() then proceed to dereference the uninitialized socket\npointer, resulting in a NULL pointer dereference.\n\nThe captured NULL deref crash:\n BUG: kernel NULL pointer dereference, address: 0000000000000018\n RIP: 0010:fou_nl_add_doit (net/ipv4/fou_core.c:590 net/ipv4/fou_core.c:764)\n [...]\n Call Trace:\n \n genl_family_rcv_msg_doit.constprop.0 (net/netlink/genetlink.c:1114)\n genl_rcv_msg (net/netlink/genetlink.c:1194 net/netlink/genetlink.c:1209)\n [...]\n netlink_rcv_skb (net/netlink/af_netlink.c:2550)\n genl_rcv (net/netlink/genetlink.c:1219)\n netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)\n netlink_sendmsg (net/netlink/af_netlink.c:1894)\n __sock_sendmsg (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1))\n __sys_sendto (./include/linux/file.h:62 (discriminator 1) ./include/linux/file.h:83 (discriminator 1) net/socket.c:2183 (discriminator 1))\n __x64_sys_sendto (net/socket.c:2213 (discriminator 1) net/socket.c:2209 (discriminator 1) net/socket.c:2209 (discriminator 1))\n do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))\n entry_SYSCALL_64_after_hwframe (net/arch/x86/entry/entry_64.S:130)\n\nThis patch makes udp_sock_create6 return -EPFNOSUPPORT instead, so\ncallers correctly take their error paths. There is only one caller of\nthe vulnerable function and only privileged users can trigger it.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "dfc96ae0074cc47b5478a59e5aa19233e434243f" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "66117dbb3dbae82f86735bf727b1d59cc677afa1" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "ba7c9ddcdd077942b798979edb035207374d4096" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "a05a2149386f6dfb4245f522acdbef892acafc84" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "9f036aa0fe46c19e938f03d10e02c23f4fffae5e" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "003343985f26dfefd0c94b1fe1316a2de74428b9" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "12aa4b73a67d95bc739995a2d6943aec2f9785c9" }, { "version": "fd384412e199b62c3ddaabd18dce86d0e164c5b9", "status": "affected", "versionType": "git", "lessThan": "b3a6df291fecf5f8a308953b65ca72b7fc9e015d" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "3.18", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "3.18" }, { "version": "5.10.253", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.203", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.167", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.130", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.78", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.20", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "6.19.10", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.19.*" }, { "version": "7.0", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }