{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-31636", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.125Z", "datePublished": "2026-04-24T14:44:50.637Z", "dateUpdated": "2026-08-05T12:24:00.729Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:24:00.729Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: fix RESPONSE authenticator parser OOB read\n\nrxgk_verify_authenticator() copies auth_len bytes into a temporary\nbuffer and then passes p + auth_len as the parser limit to\nrxgk_do_verify_authenticator(). Since p is a __be32 *, that inflates the\nparser end pointer by a factor of four and lets malformed RESPONSE\nauthenticators read past the kmalloc() buffer.\n\nDecoded from the original latest-net reproduction logs with\nscripts/decode_stacktrace.sh:\n\nBUG: KASAN: slab-out-of-bounds in rxgk_verify_response()\nCall Trace:\n dump_stack_lvl() [lib/dump_stack.c:123]\n print_report() [mm/kasan/report.c:379 mm/kasan/report.c:482]\n kasan_report() [mm/kasan/report.c:597]\n rxgk_verify_response()\n [net/rxrpc/rxgk.c:1103 net/rxrpc/rxgk.c:1167\n net/rxrpc/rxgk.c:1274]\n rxrpc_process_connection()\n [net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364\n net/rxrpc/conn_event.c:386]\n process_one_work() [kernel/workqueue.c:3281]\n worker_thread()\n [kernel/workqueue.c:3353 kernel/workqueue.c:3440]\n kthread() [kernel/kthread.c:436]\n ret_from_fork() [arch/x86/kernel/process.c:164]\n\nAllocated by task 54:\n rxgk_verify_response()\n [include/linux/slab.h:954 net/rxrpc/rxgk.c:1155\n net/rxrpc/rxgk.c:1274]\n rxrpc_process_connection()\n [net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364\n net/rxrpc/conn_event.c:386]\n\nConvert the byte count to __be32 units before constructing the parser\nlimit." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H", "baseScore": 9.1, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The vulnerable rxgk RESPONSE authenticator parser is reached by network RxRPC packets delivered over UDP to an AF_RXRPC service connection.\nAC:L - There is no race or condition outside the attacker's control; a peer can initiate the handshake, receive the challenge, and send malformed RESPONSE data to drive the parser.\nPR:N - The packet is processed while the server connection is still in RXRPC_CONN_SERVICE_CHALLENGING, before the connection is accepted as authenticated.\nUI:N - No victim user action is required beyond the RxRPC service being reachable and processing incoming network traffic.\nS:U - The impact remains within the kernel/RxRPC service security authority and does not cross a VM, IOMMU, or comparable scope boundary.\nC:H - The byte-count versus __be32 pointer arithmetic bug lets the parser read well beyond the kmalloc authenticator buffer at attacker-influenced offsets, and the overread is not strictly bounded to a few bytes.\nI:N - The flaw is an out-of-bounds read and does not provide an arbitrary write or control-flow modification primitive.\nA:H - The fix commit documents a KASAN slab-out-of-bounds report in the RESPONSE processing path, and malformed network responses can repeatedly trigger kernel fault/panic behavior." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/rxrpc/rxgk.c" ], "versions": [ { "version": "9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a", "lessThan": "7875f3d9777bd4e9892c4db830571ab8ac2044c0", "status": "affected", "versionType": "git" }, { "version": "9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a", "lessThan": "20a188775a9a9982d1987e12660d9b44b40a6c99", "status": "affected", "versionType": "git" }, { "version": "9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a", "lessThan": "3e3138007887504ee9206d0bfb5acb062c600025", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/rxrpc/rxgk.c" ], "versions": [ { "version": "6.16", "status": "affected" }, { "version": "0", "lessThan": "6.16", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.23", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.13", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "6.16", "versionEndExcluding": "6.18.23" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "6.19.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/7875f3d9777bd4e9892c4db830571ab8ac2044c0" }, { "url": "https://git.kernel.org/stable/c/20a188775a9a9982d1987e12660d9b44b40a6c99" }, { "url": "https://git.kernel.org/stable/c/3e3138007887504ee9206d0bfb5acb062c600025" } ], "title": "rxrpc: fix RESPONSE authenticator parser OOB read", "x_generator": { "engine": "bippy-1.2.0" } } } }