{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-05-05T02:49:59.365","vulnerabilities":[{"cve":{"id":"CVE-2023-52523","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2024-03-02T22:15:48.213","lastModified":"2025-01-13T19:57:06.317","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, sockmap: Reject sk_msg egress redirects to non-TCP sockets\n\nWith a SOCKMAP/SOCKHASH map and an sk_msg program user can steer messages\nsent from one TCP socket (s1) to actually egress from another TCP\nsocket (s2):\n\ntcp_bpf_sendmsg(s1)\t\t// = sk_prot->sendmsg\n  tcp_bpf_send_verdict(s1)\t// __SK_REDIRECT case\n    tcp_bpf_sendmsg_redir(s2)\n      tcp_bpf_push_locked(s2)\n\ttcp_bpf_push(s2)\n\t  tcp_rate_check_app_limited(s2) // expects tcp_sock\n\t  tcp_sendmsg_locked(s2)\t // ditto\n\nThere is a hard-coded assumption in the call-chain, that the egress\nsocket (s2) is a TCP socket.\n\nHowever in commit 122e6c79efe1 (\"sock_map: Update sock type checks for\nUDP\") we have enabled redirects to non-TCP sockets. This was done for the\nsake of BPF sk_skb programs. There was no indention to support sk_msg\nsend-to-egress use case.\n\nAs a result, attempts to send-to-egress through a non-TCP socket lead to a\ncrash due to invalid downcast from sock to tcp_sock:\n\n BUG: kernel NULL pointer dereference, address: 000000000000002f\n ...\n Call Trace:\n  <TASK>\n  ? show_regs+0x60/0x70\n  ? __die+0x1f/0x70\n  ? page_fault_oops+0x80/0x160\n  ? do_user_addr_fault+0x2d7/0x800\n  ? rcu_is_watching+0x11/0x50\n  ? exc_page_fault+0x70/0x1c0\n  ? asm_exc_page_fault+0x27/0x30\n  ? tcp_tso_segs+0x14/0xa0\n  tcp_write_xmit+0x67/0xce0\n  __tcp_push_pending_frames+0x32/0xf0\n  tcp_push+0x107/0x140\n  tcp_sendmsg_locked+0x99f/0xbb0\n  tcp_bpf_push+0x19d/0x3a0\n  tcp_bpf_sendmsg_redir+0x55/0xd0\n  tcp_bpf_send_verdict+0x407/0x550\n  tcp_bpf_sendmsg+0x1a1/0x390\n  inet_sendmsg+0x6a/0x70\n  sock_sendmsg+0x9d/0xc0\n  ? sockfd_lookup_light+0x12/0x80\n  __sys_sendto+0x10e/0x160\n  ? syscall_enter_from_user_mode+0x20/0x60\n  ? __this_cpu_preempt_check+0x13/0x20\n  ? lockdep_hardirqs_on+0x82/0x110\n  __x64_sys_sendto+0x1f/0x30\n  do_syscall_64+0x38/0x90\n  entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nReject selecting a non-TCP sockets as redirect target from a BPF sk_msg\nprogram to prevent the crash. When attempted, user will receive an EACCES\nerror from send/sendto/sendmsg() syscall."},{"lang":"es","value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf, sockmap: rechaza las redirecciones de salida de sk_msg a sockets que no son TCP. Con un mapa SOCKMAP/SOCKHASH y un programa sk_msg, el usuario puede dirigir los mensajes enviados desde un socket TCP (s1) para que realmente salgan desde otro socket TCP (s2): tcp_bpf_sendmsg(s1) // = sk_prot-&gt;sendmsg tcp_bpf_send_verdict(s1) // __SK_REDIRECT caso tcp_bpf_sendmsg_redir(s2) tcp_bpf_push_locked(s2) tcp_bpf_push(s2) tcp_rate_check_ app_limited(s2) // espera tcp_sock tcp_sendmsg_locked(s2 ) // ídem Hay una suposición codificada en la cadena de llamadas de que el socket de salida (s2) es un socket TCP. Sin embargo, en el commit 122e6c79efe1 (\"sock_map: Actualizar comprobaciones de tipo de calcetín para UDP\") hemos habilitado redirecciones a sockets que no son TCP. Esto se hizo por el bien de los programas BPF sk_skb. No había ninguna sangría para admitir el caso de uso de envío a salida de sk_msg. Como resultado, los intentos de envío a salida a través de un socket que no es TCP provocan un bloqueo debido a una conversión no válida de sock a tcp_sock: ERROR: desreferencia del puntero NULL del núcleo, dirección: 0000000000000002f... Seguimiento de llamadas: . mostrar_regs+0x60/0x70? __die+0x1f/0x70 ? page_fault_oops+0x80/0x160? do_user_addr_fault+0x2d7/0x800? rcu_is_watching+0x11/0x50? exc_page_fault+0x70/0x1c0? asm_exc_page_fault+0x27/0x30? tcp_tso_segs+0x14/0xa0 tcp_write_xmit+0x67/0xce0 __tcp_push_pending_frames+0x32/0xf0 tcp_push+0x107/0x140 tcp_sendmsg_locked+0x99f/0xbb0 tcp_bpf_push+0x19d/0x3a0 tcp_bpf_sendmsg_redir+0x55/0xd0 tcp_bpf_send_verdict+0x407/0x550 tcp_bpf_sendmsg+0x1a1/0x390 inet_sendmsg+0x6a/0x70 sock_sendmsg+0x9d/0xc0? sockfd_lookup_light+0x12/0x80 __sys_sendto+0x10e/0x160 ? syscall_enter_from_user_mode+0x20/0x60? __this_cpu_preempt_check+0x13/0x20? lockdep_hardirqs_on+0x82/0x110 __x64_sys_sendto+0x1f/0x30 do_syscall_64+0x38/0x90 Entry_SYSCALL_64_after_hwframe+0x63/0xcd Rechace la selección de sockets que no sean TCP como destino de redireccionamiento desde un programa BPF sk_msg para evitar el bloqueo. Cuando lo intente, el usuario recibirá un error EACCES de la llamada al sistema send/sendto/sendmsg()."}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"CWE-476"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"5.15.135","matchCriteriaId":"0988674C-BFC5-4018-840B-F6E3C9B45A62"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.57","matchCriteriaId":"8629E5D1-351D-4D4B-8D05-E10BD4A1CFD0"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.5.7","matchCriteriaId":"830A824C-F212-4FDC-ADEF-0EBEC6B2365B"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.6:rc1:*:*:*:*:*:*","matchCriteriaId":"84267A4F-DBC2-444F-B41D-69E15E1BEC97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.6:rc2:*:*:*:*:*:*","matchCriteriaId":"FB440208-241C-4246-9A83-C1715C0DAA6C"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.6:rc3:*:*:*:*:*:*","matchCriteriaId":"0DC421F1-3D5A-4BEF-BF76-4E468985D20B"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.6:rc4:*:*:*:*:*:*","matchCriteriaId":"00AB783B-BE05-40E8-9A55-6AA457D95031"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/b80e31baa43614e086a9d29dc1151932b1bd7fc5","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/b8f97e47b6fb84fcf2f5a22e725eefb6cf5070c2","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/bc8b89b6963803a123f64aa9494155a037b3d728","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/ded6e448028f0f91b6af35985afca01fa02a9089","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/b80e31baa43614e086a9d29dc1151932b1bd7fc5","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/b8f97e47b6fb84fcf2f5a22e725eefb6cf5070c2","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/bc8b89b6963803a123f64aa9494155a037b3d728","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/ded6e448028f0f91b6af35985afca01fa02a9089","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]}]}}]}