{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-46043", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-13T15:03:33.094Z", "datePublished": "2026-05-27T12:56:57.987Z", "dateUpdated": "2026-08-05T12:29:19.068Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:29:19.068Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv\n\nrxe_rcv() currently checks only that the incoming packet is at least\nheader_size(pkt) bytes long before payload_size() is used.\n\nHowever, payload_size() subtracts both the attacker-controlled BTH pad\nfield and RXE_ICRC_SIZE from pkt->paylen:\n\n payload_size = pkt->paylen - offset[RXE_PAYLOAD] - bth_pad(pkt)\n - RXE_ICRC_SIZE\n\nThis means a short packet can still make payload_size() underflow even\nif it includes enough bytes for the fixed headers. Simply requiring\nheader_size(pkt) + RXE_ICRC_SIZE is not sufficient either, because a\npacket with a forged non-zero BTH pad can still leave payload_size()\nnegative and pass an underflowed value to later receive-path users.\n\nFix this by validating pkt->paylen against the full minimum length\nrequired by payload_size(): header_size(pkt) + bth_pad(pkt) +\nRXE_ICRC_SIZE." } ], "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 code processes RoCEv2 packets received over UDP/IP (port 4791) from a remote peer; `pkt->paylen` is derived directly from the attacker-controlled UDP length header field.\nAC:L - A single crafted packet with `paylen` at the header-size boundary and a non-zero BTH pad deterministically underflows `payload_size()`; the resulting ~2⁶⁴-byte read reliably runs off the buffer with no race or unknowable memory layout required.\nPR:N - A remote, unauthenticated attacker triggers it; via the multicast path `hdr_check()` returns success with no QP, so `rxe_icrc_check()` performs the OOB read with no established connection or credentials.\nUI:N - The packet is processed automatically in the receive path on arrival; no victim action is required.\nS:U - The fault and its impact are confined to the kernel's own memory/security scope; there is no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The integer underflow produces an unbounded out-of-bounds read length passed to the CRC/copy routines; per the rubric an unbounded OOB read is High confidentiality impact.\nI:N - The underflow is used purely as a read length; the downstream copy/write consumers are guarded by length checks and a negative truncated length makes the copy a no-op, so no memory is modified.\nA:H - The near-2⁶⁴-byte out-of-bounds read in `rxe_crc32()` walks off the skb buffer into unmapped memory, causing a kernel oops/panic." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/infiniband/sw/rxe/rxe_recv.c" ], "versions": [ { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "c4376c672c3648d5bdc31dfffc329d07164f93c4", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "5fedefec757192dcaad29a664ac332c7601be144", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "2c0d71ef12f46c57d37bc571f3f2797db7eb50cc", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "2fd4f8b749309a61c3f3f88ee8891d94f79e1240", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "f83519a4c122c9c7a850a2197648a9ff4c67c520", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "9b924f3a26b21330a837cfe72e819b6393bbeeaa", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "e8ee0e792d475b1067c199ef0af1b6221fa6f43d", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "7244491dab347f648e661da96dc0febadd9daec3", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/infiniband/sw/rxe/rxe_recv.c" ], "versions": [ { "version": "4.8", "status": "affected" }, { "version": "0", "lessThan": "4.8", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.258", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.209", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.140", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.86", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.27", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.4", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "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": "4.8", "versionEndExcluding": "5.10.258" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "5.15.209" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.6.140" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.12.86" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.18.27" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "7.0.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c4376c672c3648d5bdc31dfffc329d07164f93c4" }, { "url": "https://git.kernel.org/stable/c/5fedefec757192dcaad29a664ac332c7601be144" }, { "url": "https://git.kernel.org/stable/c/2c0d71ef12f46c57d37bc571f3f2797db7eb50cc" }, { "url": "https://git.kernel.org/stable/c/2fd4f8b749309a61c3f3f88ee8891d94f79e1240" }, { "url": "https://git.kernel.org/stable/c/f83519a4c122c9c7a850a2197648a9ff4c67c520" }, { "url": "https://git.kernel.org/stable/c/9b924f3a26b21330a837cfe72e819b6393bbeeaa" }, { "url": "https://git.kernel.org/stable/c/e8ee0e792d475b1067c199ef0af1b6221fa6f43d" }, { "url": "https://git.kernel.org/stable/c/7244491dab347f648e661da96dc0febadd9daec3" } ], "title": "RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv", "x_generator": { "engine": "bippy-1.2.0" } } } }