{"api_version":"1","generated_at":"2026-05-28T15:54:17+00:00","cve":"CVE-2026-46133","urls":{"html":"https://cve.report/CVE-2026-46133","api":"https://cve.report/api/cve/CVE-2026-46133.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-46133","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-46133"},"summary":{"title":"RDMA/rxe: Reject unknown opcodes before ICRC processing","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Reject unknown opcodes before ICRC processing\n\nEven after applying commit 7244491dab34 (\"RDMA/rxe: Validate pad and ICRC\nbefore payload_size() in rxe_rcv\"), a single unauthenticated UDP packet\ncan still trigger panic.  That patch handled payload_size() underflow only\nfor valid opcodes with short packets, not for packets carrying an unknown\nopcode.  The unknown-opcode OOB read described below predates that commit\nand reaches back to the initial Soft RoCE driver.\n\nThe check added there reads\n\n    pkt->paylen < header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhere header_size(pkt) expands to rxe_opcode[pkt->opcode].length.  The\nrxe_opcode[] array has 256 entries but is only populated for defined IB\nopcodes; any other entry (for example opcode 0xff) is zero-initialized, so\nlength == 0 and the check degenerates to\n\n    pkt->paylen < 0 + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhich does not constrain pkt->paylen enough.  rxe_icrc_hdr() then computes\n\n    rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES\n\nwhich underflows when length == 0 and passes a huge value to rxe_crc32(),\ncausing an out-of-bounds read of the skb payload.\n\nReproduced on v7.0-rc7 with that fix applied, QEMU/KVM with\nCONFIG_RDMA_RXE=y and CONFIG_KASAN=y, after\n\n    rdma link add rxe0 type rxe netdev eth0\n\nA single 48-byte UDP packet to port 4791 with BTH opcode=0xff and\nQPN=IB_MULTICAST_QPN triggers:\n\n    BUG: KASAN: slab-out-of-bounds in crc32_le+0x115/0x170\n    Read of size 1 at addr ...\n    The buggy address is located 0 bytes to the right of\n     allocated 704-byte region\n    Call Trace:\n     crc32_le+0x115/0x170\n     rxe_icrc_hdr.isra.0+0x226/0x300\n     rxe_icrc_check+0x13f/0x3a0\n     rxe_rcv+0x6e1/0x16e0\n     rxe_udp_encap_recv+0x20a/0x320\n     udp_queue_rcv_one_skb+0x7ed/0x12c0\n\nSubsequent packets with the same shape fault on unmapped memory and panic\nthe kernel.  The trigger requires only module load and \"rdma link add\"; no\nQP, no connection, and no authentication.\n\nFix this by rejecting packets whose opcode has no rxe_opcode[] entry,\ndetected via the zero mask or zero length, before any length arithmetic\nruns.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-28 10:16:28","updated_at":"2026-05-28 13:44:01"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/4c6f86d85d03cdb33addce86aa69aa795ca6c47a","name":"https://git.kernel.org/stable/c/4c6f86d85d03cdb33addce86aa69aa795ca6c47a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6fa18025e5782afff91415fd5217b39c1e4837d7","name":"https://git.kernel.org/stable/c/6fa18025e5782afff91415fd5217b39c1e4837d7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f8ee926431a7bbec2b10c1290664af2cb290b983","name":"https://git.kernel.org/stable/c/f8ee926431a7bbec2b10c1290664af2cb290b983","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e3dc3a2fb05f4ed49c7f20594c4c52350d032189","name":"https://git.kernel.org/stable/c/e3dc3a2fb05f4ed49c7f20594c4c52350d032189","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/006a3a5f75345c6a0dbf13fd3ee01406e93b6733","name":"https://git.kernel.org/stable/c/006a3a5f75345c6a0dbf13fd3ee01406e93b6733","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-46133","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46133","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8700e3e7c4857d28ebaa824509934556da0b3e76 e3dc3a2fb05f4ed49c7f20594c4c52350d032189 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8700e3e7c4857d28ebaa824509934556da0b3e76 f8ee926431a7bbec2b10c1290664af2cb290b983 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8700e3e7c4857d28ebaa824509934556da0b3e76 006a3a5f75345c6a0dbf13fd3ee01406e93b6733 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8700e3e7c4857d28ebaa824509934556da0b3e76 6fa18025e5782afff91415fd5217b39c1e4837d7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8700e3e7c4857d28ebaa824509934556da0b3e76 4c6f86d85d03cdb33addce86aa69aa795ca6c47a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.8","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.8 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.140 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.88 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.30 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.7 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1-rc3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/infiniband/sw/rxe/rxe_recv.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"e3dc3a2fb05f4ed49c7f20594c4c52350d032189","status":"affected","version":"8700e3e7c4857d28ebaa824509934556da0b3e76","versionType":"git"},{"lessThan":"f8ee926431a7bbec2b10c1290664af2cb290b983","status":"affected","version":"8700e3e7c4857d28ebaa824509934556da0b3e76","versionType":"git"},{"lessThan":"006a3a5f75345c6a0dbf13fd3ee01406e93b6733","status":"affected","version":"8700e3e7c4857d28ebaa824509934556da0b3e76","versionType":"git"},{"lessThan":"6fa18025e5782afff91415fd5217b39c1e4837d7","status":"affected","version":"8700e3e7c4857d28ebaa824509934556da0b3e76","versionType":"git"},{"lessThan":"4c6f86d85d03cdb33addce86aa69aa795ca6c47a","status":"affected","version":"8700e3e7c4857d28ebaa824509934556da0b3e76","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/infiniband/sw/rxe/rxe_recv.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.8"},{"lessThan":"4.8","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.140","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.88","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.30","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1-rc3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.140","versionStartIncluding":"4.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.88","versionStartIncluding":"4.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.30","versionStartIncluding":"4.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.7","versionStartIncluding":"4.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1-rc3","versionStartIncluding":"4.8","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Reject unknown opcodes before ICRC processing\n\nEven after applying commit 7244491dab34 (\"RDMA/rxe: Validate pad and ICRC\nbefore payload_size() in rxe_rcv\"), a single unauthenticated UDP packet\ncan still trigger panic.  That patch handled payload_size() underflow only\nfor valid opcodes with short packets, not for packets carrying an unknown\nopcode.  The unknown-opcode OOB read described below predates that commit\nand reaches back to the initial Soft RoCE driver.\n\nThe check added there reads\n\n    pkt->paylen < header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhere header_size(pkt) expands to rxe_opcode[pkt->opcode].length.  The\nrxe_opcode[] array has 256 entries but is only populated for defined IB\nopcodes; any other entry (for example opcode 0xff) is zero-initialized, so\nlength == 0 and the check degenerates to\n\n    pkt->paylen < 0 + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhich does not constrain pkt->paylen enough.  rxe_icrc_hdr() then computes\n\n    rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES\n\nwhich underflows when length == 0 and passes a huge value to rxe_crc32(),\ncausing an out-of-bounds read of the skb payload.\n\nReproduced on v7.0-rc7 with that fix applied, QEMU/KVM with\nCONFIG_RDMA_RXE=y and CONFIG_KASAN=y, after\n\n    rdma link add rxe0 type rxe netdev eth0\n\nA single 48-byte UDP packet to port 4791 with BTH opcode=0xff and\nQPN=IB_MULTICAST_QPN triggers:\n\n    BUG: KASAN: slab-out-of-bounds in crc32_le+0x115/0x170\n    Read of size 1 at addr ...\n    The buggy address is located 0 bytes to the right of\n     allocated 704-byte region\n    Call Trace:\n     crc32_le+0x115/0x170\n     rxe_icrc_hdr.isra.0+0x226/0x300\n     rxe_icrc_check+0x13f/0x3a0\n     rxe_rcv+0x6e1/0x16e0\n     rxe_udp_encap_recv+0x20a/0x320\n     udp_queue_rcv_one_skb+0x7ed/0x12c0\n\nSubsequent packets with the same shape fault on unmapped memory and panic\nthe kernel.  The trigger requires only module load and \"rdma link add\"; no\nQP, no connection, and no authentication.\n\nFix this by rejecting packets whose opcode has no rxe_opcode[] entry,\ndetected via the zero mask or zero length, before any length arithmetic\nruns."}],"providerMetadata":{"dateUpdated":"2026-05-28T09:35:47.819Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/e3dc3a2fb05f4ed49c7f20594c4c52350d032189"},{"url":"https://git.kernel.org/stable/c/f8ee926431a7bbec2b10c1290664af2cb290b983"},{"url":"https://git.kernel.org/stable/c/006a3a5f75345c6a0dbf13fd3ee01406e93b6733"},{"url":"https://git.kernel.org/stable/c/6fa18025e5782afff91415fd5217b39c1e4837d7"},{"url":"https://git.kernel.org/stable/c/4c6f86d85d03cdb33addce86aa69aa795ca6c47a"}],"title":"RDMA/rxe: Reject unknown opcodes before ICRC processing","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-46133","datePublished":"2026-05-28T09:35:47.819Z","dateReserved":"2026-05-13T15:03:33.099Z","dateUpdated":"2026-05-28T09:35:47.819Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-28 10:16:28","lastModifiedDate":"2026-05-28 13:44:01","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"46133","Ordinal":"1","Title":"RDMA/rxe: Reject unknown opcodes before ICRC processing","CVE":"CVE-2026-46133","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"46133","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Reject unknown opcodes before ICRC processing\n\nEven after applying commit 7244491dab34 (\"RDMA/rxe: Validate pad and ICRC\nbefore payload_size() in rxe_rcv\"), a single unauthenticated UDP packet\ncan still trigger panic.  That patch handled payload_size() underflow only\nfor valid opcodes with short packets, not for packets carrying an unknown\nopcode.  The unknown-opcode OOB read described below predates that commit\nand reaches back to the initial Soft RoCE driver.\n\nThe check added there reads\n\n    pkt->paylen < header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhere header_size(pkt) expands to rxe_opcode[pkt->opcode].length.  The\nrxe_opcode[] array has 256 entries but is only populated for defined IB\nopcodes; any other entry (for example opcode 0xff) is zero-initialized, so\nlength == 0 and the check degenerates to\n\n    pkt->paylen < 0 + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhich does not constrain pkt->paylen enough.  rxe_icrc_hdr() then computes\n\n    rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES\n\nwhich underflows when length == 0 and passes a huge value to rxe_crc32(),\ncausing an out-of-bounds read of the skb payload.\n\nReproduced on v7.0-rc7 with that fix applied, QEMU/KVM with\nCONFIG_RDMA_RXE=y and CONFIG_KASAN=y, after\n\n    rdma link add rxe0 type rxe netdev eth0\n\nA single 48-byte UDP packet to port 4791 with BTH opcode=0xff and\nQPN=IB_MULTICAST_QPN triggers:\n\n    BUG: KASAN: slab-out-of-bounds in crc32_le+0x115/0x170\n    Read of size 1 at addr ...\n    The buggy address is located 0 bytes to the right of\n     allocated 704-byte region\n    Call Trace:\n     crc32_le+0x115/0x170\n     rxe_icrc_hdr.isra.0+0x226/0x300\n     rxe_icrc_check+0x13f/0x3a0\n     rxe_rcv+0x6e1/0x16e0\n     rxe_udp_encap_recv+0x20a/0x320\n     udp_queue_rcv_one_skb+0x7ed/0x12c0\n\nSubsequent packets with the same shape fault on unmapped memory and panic\nthe kernel.  The trigger requires only module load and \"rdma link add\"; no\nQP, no connection, and no authentication.\n\nFix this by rejecting packets whose opcode has no rxe_opcode[] entry,\ndetected via the zero mask or zero length, before any length arithmetic\nruns.","Type":"Description","Title":"RDMA/rxe: Reject unknown opcodes before ICRC processing"}]}}}