{"id":"CVE-2026-68141","state":"PUBLISHED","title":"net/af_iucv: fix NULL deref in afiucv_hs_callback_syn()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/af_iucv: fix NULL deref in afiucv_hs_callback_syn()\n\nafiucv_hs_callback_syn() allocates the child socket with GFP_ATOMIC.\nIf the allocation fails, nsk is NULL.\n\nThe connection-refused path is entered when the listen state check\nfails, the accept backlog is full, or nsk is NULL. The code\nunconditionally calls iucv_sock_kill(nsk) in that path.\n\niucv_sock_kill() does not accept a NULL socket pointer and immediately\ndereferences sk via sock_flag(sk, SOCK_ZAPPED). When nsk is NULL,\ncalling iucv_sock_kill(nsk) results in a NULL pointer dereference.\n\nOnly call iucv_sock_kill() when a child socket was successfully\nallocated.","publishedAt":"2026-08-10T11:59:05.051Z","updatedAt":"2026-10-19T20:58:53.262Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"6a1eb5b46c19073f8153b7e2c19b408cf353aaf1","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"c0b6e2ae90613c2fea7eaf3faa20985c6c2a1953","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"07e21deb3664001995e0a456dd627ab7dbe127ec","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"8bb111f87ded6acb9837ec9b45d6f02cda94c51f","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"46453b16f38ec7147351f7447e2aec6ea330f7b3","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"33736ff5e7c97d3348ce812e8bd2e125d840743c","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"0e857185591fe79934427c9c0c1c31dc776be134","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"47a5116e56a6b6fe1e909f244e39cd0fc26ceee4","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/iucv/af_iucv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.2","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.6","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/iucv/af_iucv.c"]}],"references":["https://git.kernel.org/stable/c/6a1eb5b46c19073f8153b7e2c19b408cf353aaf1","https://git.kernel.org/stable/c/c0b6e2ae90613c2fea7eaf3faa20985c6c2a1953","https://git.kernel.org/stable/c/07e21deb3664001995e0a456dd627ab7dbe127ec","https://git.kernel.org/stable/c/8bb111f87ded6acb9837ec9b45d6f02cda94c51f","https://git.kernel.org/stable/c/46453b16f38ec7147351f7447e2aec6ea330f7b3","https://git.kernel.org/stable/c/33736ff5e7c97d3348ce812e8bd2e125d840743c","https://git.kernel.org/stable/c/0e857185591fe79934427c9c0c1c31dc776be134","https://git.kernel.org/stable/c/47a5116e56a6b6fe1e909f244e39cd0fc26ceee4"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/68xxx/CVE-2026-68141.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-68141","state":"PUBLISHED","datePublished":"2026-08-10T11:59:05.051Z","dateUpdated":"2026-10-19T20:58:53.262Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-30T09:28:09.370Z"},"containers":{"cna":{"title":"net/af_iucv: fix NULL deref in afiucv_hs_callback_syn()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/af_iucv: fix NULL deref in afiucv_hs_callback_syn()\n\nafiucv_hs_callback_syn() allocates the child socket with GFP_ATOMIC.\nIf the allocation fails, nsk is NULL.\n\nThe connection-refused path is entered when the listen state check\nfails, the accept backlog is full, or nsk is NULL. The code\nunconditionally calls iucv_sock_kill(nsk) in that path.\n\niucv_sock_kill() does not accept a NULL socket pointer and immediately\ndereferences sk via sock_flag(sk, SOCK_ZAPPED). When nsk is NULL,\ncalling iucv_sock_kill(nsk) results in a NULL pointer dereference.\n\nOnly call iucv_sock_kill() when a child socket was successfully\nallocated."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"6a1eb5b46c19073f8153b7e2c19b408cf353aaf1","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"c0b6e2ae90613c2fea7eaf3faa20985c6c2a1953","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"07e21deb3664001995e0a456dd627ab7dbe127ec","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"8bb111f87ded6acb9837ec9b45d6f02cda94c51f","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"46453b16f38ec7147351f7447e2aec6ea330f7b3","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"33736ff5e7c97d3348ce812e8bd2e125d840743c","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"0e857185591fe79934427c9c0c1c31dc776be134","versionType":"git"},{"version":"3881ac441f642d56503818123446f7298442236b","status":"affected","lessThan":"47a5116e56a6b6fe1e909f244e39cd0fc26ceee4","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/iucv/af_iucv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.2","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.6","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/iucv/af_iucv.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/6a1eb5b46c19073f8153b7e2c19b408cf353aaf1"},{"url":"https://git.kernel.org/stable/c/c0b6e2ae90613c2fea7eaf3faa20985c6c2a1953"},{"url":"https://git.kernel.org/stable/c/07e21deb3664001995e0a456dd627ab7dbe127ec"},{"url":"https://git.kernel.org/stable/c/8bb111f87ded6acb9837ec9b45d6f02cda94c51f"},{"url":"https://git.kernel.org/stable/c/46453b16f38ec7147351f7447e2aec6ea330f7b3"},{"url":"https://git.kernel.org/stable/c/33736ff5e7c97d3348ce812e8bd2e125d840743c"},{"url":"https://git.kernel.org/stable/c/0e857185591fe79934427c9c0c1c31dc776be134"},{"url":"https://git.kernel.org/stable/c/47a5116e56a6b6fe1e909f244e39cd0fc26ceee4"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - The flaw is reached from afiucv_hs_rcv() via dev_add_pack() when ETH_P_AF_IUCV SYN frames arrive on a HiperSockets netdev in netif RX softirq; a remote LPAR/guest on the IBM Z HiperSockets fabric can send these connection requests without local access.\nAC:L - An attacker can repeatedly send SYN packets to a listening AF_IUCV service to pressure GFP_ATOMIC socket allocations until iucv_sock_alloc() fails and the broken connection-refused path runs; no timing race or victim-specific state beyond routine memory pressure is required.\nPR:N - Exploitation requires only sending unauthenticated HiperSockets SYN traffic to a bound/listening AF_IUCV socket; the handshake path has no credential checks and the af_iucv code performs no capability or permission validation before reaching afiucv_hs_callback_syn().\nUI:N - Triggering the NULL dereference needs no action from an end user beyond a service already listening on HiperSockets; the attacker can initiate SYN packets remotely without victim interaction.\nS:U - Impact is a kernel NULL pointer dereference and likely oops/panic in the victim LPAR kernel; it does not cross a VM/host, IOMMU, or sandbox boundary to compromise a different security authority.\nC:N - The failure is an immediate NULL pointer dereference in sock_flag() inside iucv_sock_kill(); there is no memory corruption, out-of-bounds access, or use-after-free that could yield information disclosure.\nI:N - The bug does not write attacker-controlled data or corrupt kernel structures; it only dereferences a NULL socket pointer during cleanup, so no integrity impact or code-execution primitive is created.\nA:H - A NULL dereference in afiucv_hs_callback_syn() during softirq packet processing can cause a kernel oops or panic, denying all service on the affected IBM Z LPAR until reboot."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-19T16:29:59.584Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"5.10.265"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"5.15.216"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"7.1.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-68141","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-16T15:44:37.607380Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","lang":"en","type":"CWE","description":"CWE-476 NULL Pointer Dereference"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:58:53.262Z"}}]}}}