{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74435", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.896Z", "datePublished": "2026-08-15T05:59:34.073Z", "dateUpdated": "2026-08-17T05:47:09.898Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:47:09.898Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: rxrpc_verify_data ensure rx_dec_buffer alloc\n\nrxrpc_recvmsg_data() calls rxrpc_verify_data() whenever the\nrxrpc_call.rx_dec_buffer is unallocated and assumes that upon\nsuccessful return that rx_dec_buffer must be allocated.\nHowever, rxrpc_verify_data() does not request an allocation if\nthe rxrpc_skb_priv.len is zero.\n\nIn addition, failure to allocate rx_dec_buffer will result in a\ncall to skb_copy_bits() with a NULL destination which can\ntrigger a NULL pointer dereference.\n\nTo prevent these issues rxrpc_verify_data() is modified to\nalways attempt to allocate the rxrpc_call.rx_dec_buffer if it\nis NULL.\n\nThis issue was identified with assistance of a private\nsashiko instance." } ], "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 - RxRPC runs over UDP/IP; a remote peer can deliver crafted DATA packets that are queued on the receive path and later processed in rxrpc_verify_data() via recvmsg/kernel_recv_data, with no local access required.\nAC:L - An attacker can reliably trigger the bug by sending a zero-length RxRPC DATA packet (header-only skb so sp->len==0) to a listening service; no races or victim-specific state are needed beyond an active RxRPC/AFS endpoint.\nPR:N - Incoming DATA packets are accepted and queued on new calls before Kerberos authentication completes, so an unauthenticated remote attacker can reach the vulnerable recvmsg path on internet-facing AFS/RxRPC servers without any local privileges.\nUI:N - On AFS/RxRPC servers the kernel automatically receives network DATA, queues it, and invokes rxrpc_kernel_recv_data through service callbacks; exploitation requires no victim user action such as mounting a filesystem or opening a file.\nS:U - The flaw causes a kernel NULL pointer dereference during in-kernel packet processing on the same host running the RxRPC/AFS service; it does not cross a VM, container, or IOMMU security boundary.\nC:N - The failure mode is a NULL pointer dereference in skb_copy_bits()/subsequent recvmsg handling when rx_dec_buffer was never allocated; this is a pure crash path with no demonstrated or plausible arbitrary kernel memory read or information disclosure.\nI:N - No memory corruption, arbitrary write, or code-execution primitive is introduced; the bug dereferences a NULL decryption buffer during receive processing and results in kernel oops/panic rather than controlled data modification.\nA:H - A successful trigger causes a kernel NULL pointer dereference during recvmsg data verification/decryption, which can oops or panic the host and deny service to all workloads on affected AFS/RxRPC servers until reboot." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/rxrpc/recvmsg.c" ], "versions": [ { "version": "a05bf6d9e621fa71e89ccebe3047ba45218d7b38", "lessThan": "8bbede0afced346b24e4fbde0c68cf12980ba948", "status": "affected", "versionType": "git" }, { "version": "b94a6ccbaf1104dd980150a65fdeb2f69d17d2f5", "lessThan": "6563b4eb38c35d75892445bcf8aacdc29914821c", "status": "affected", "versionType": "git" }, { "version": "46cb765e2e5ad52303ea157e10d370bb6b7acbbf", "lessThan": "d3b642cf95d48234590cc91450d8705a9bf6b540", "status": "affected", "versionType": "git" }, { "version": "d2bc90cf6c75cb96d2ce549be6c35efa3099d25b", "lessThan": "a962bc8508592c4d51092edac68579bd8b18fe44", "status": "affected", "versionType": "git" }, { "version": "d2bc90cf6c75cb96d2ce549be6c35efa3099d25b", "lessThan": "16c8ae9735c5bd7e54dd7478d6348e0fc860842d", "status": "affected", "versionType": "git" }, { "version": "c580087743712112778a06d65a4074053072d7bf", "status": "affected", "versionType": "git" }, { "version": "6.6.143", "lessThan": "6.6.145", "status": "affected", "versionType": "semver" }, { "version": "6.12.93", "lessThan": "6.12.97", "status": "affected", "versionType": "semver" }, { "version": "6.18.35", "lessThan": "6.18.40", "status": "affected", "versionType": "semver" }, { "version": "7.0.11", "lessThan": "7.1", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/rxrpc/recvmsg.c" ], "versions": [ { "version": "7.1", "status": "affected" }, { "version": "0", "lessThan": "7.1", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.143", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.93", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.35", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1", "versionEndExcluding": "7.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0.11" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8bbede0afced346b24e4fbde0c68cf12980ba948" }, { "url": "https://git.kernel.org/stable/c/6563b4eb38c35d75892445bcf8aacdc29914821c" }, { "url": "https://git.kernel.org/stable/c/d3b642cf95d48234590cc91450d8705a9bf6b540" }, { "url": "https://git.kernel.org/stable/c/a962bc8508592c4d51092edac68579bd8b18fe44" }, { "url": "https://git.kernel.org/stable/c/16c8ae9735c5bd7e54dd7478d6348e0fc860842d" } ], "title": "rxrpc: rxrpc_verify_data ensure rx_dec_buffer alloc", "x_generator": { "engine": "bippy-1.2.0" } } } }