{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-64102", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-64102", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-07-19T15:40:06.776Z", "updatedAt": "2026-10-19T20:28:11.907Z", "importedAt": "2026-10-24T01:58:25.636Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "RDMA/siw: Reject MPA FPDU length underflow before signed receive math", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/siw: Reject MPA FPDU length underflow before signed receive math\n\nA malicious connected siw peer can send an iWARP FPDU whose MPA length\nfield (c_hdr->mpa_len, 16 bit big-endian, peer-controlled) is smaller\nthan the fixed DDP/RDMAP header for the announced opcode. Soft-iWARP\nparses the full header in siw_get_hdr() based on iwarp_pktinfo[opcode]\n.hdr_len, but never compares mpa_len against that header length.\n\nsiw_tcp_rx_data() then derives\n\n srx->fpdu_part_rem = be16_to_cpu(mpa_len) - fpdu_part_rcvd\n + MPA_HDR_SIZE;\n\nwhere fpdu_part_rcvd equals iwarp_pktinfo[opcode].hdr_len at this\npoint. For a tagged WRITE (hdr_len 16, MPA_HDR_SIZE 2) the smallest\non-wire mpa_len of 0 yields fpdu_part_rem = -14, and any mpa_len below\nhdr_len - MPA_HDR_SIZE underflows to a negative int.\n\nThe signed value then flows into siw_proc_write()/siw_proc_rresp() as\n\n bytes = min(srx->fpdu_part_rem, srx->skb_new);\n\nis handed to siw_check_mem() as an int len (whose interval check\naddr + len > mem->va + mem->len is satisfied for a valid base when\nlen is negative), and reaches siw_rx_data() -> siw_rx_kva() /\nsiw_rx_umem() -> skb_copy_bits() as a signed copy length. The header\ncopy branch in skb_copy_bits() promotes that to size_t, producing a\nmulti-gigabyte read.\n\nKASAN under a KUnit harness that drives the real kernel TCP receive\npath -- a loopback AF_INET socketpair, the malformed FPDU written via\nkernel_sendmsg, sk_data_ready firing in softirq, tcp_read_sock\ndispatching to siw_tcp_rx_data -- reports:\n\n BUG: KASAN: use-after-free in skb_copy_bits+0x284/0x480\n Read of size 4294967295 at addr ffff888...\n Call Trace:\n skb_copy_bits\n siw_rx_kva\n siw_rx_data\n siw_check_mem\n siw_proc_write\n siw_tcp_rx_data\n __tcp_read_sock\n siw_qp_llp_data_ready\n tcp_data_ready\n tcp_data_queue\n\nAdd the missing invariant at the earliest point where the peer header\nis fully assembled. iwarp_pktinfo[*].hdr_len - MPA_HDR_SIZE is exactly\nthe value the siw transmitter uses as the minimum mpa_len for each\nopcode (drivers/infiniband/sw/siw/siw_qp.c:33), so this matches the\nprotocol contract. Out-of-range FPDUs terminate the connection with\nTERM_ERROR_LAYER_LLP / LLP_ETYPE_MPA / LLP_ECODE_FPDU_START -- which\nis RFC 5044 Section 8 error code 3 (\"Marker and ULPDU Length fields\ndo not agree on the start of an FPDU\"), the correct framing-error\nclass for this inconsistency.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "683f7cfbf514193d63c0efa079f3352bde84c2e0" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "4a331582011d9e8089af8aa2a61ec6b4443bb245" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "33a8b5e971e294ec2a7b74211c545e09efd8e9ac" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "14553be882d9ce91749c9d64041de66e34ad8e70" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "c7c0c0f4379dedec12d24dbb9dded5d2db7fd9f2" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "1012896f4225e8f801ff3c1648023845b66dfb11" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "775b4dc9618a99a1fa48b57554041a5dc17e1336" }, { "version": "8b6a361b8c482f22ac99c3273285ff16b23fba91", "status": "affected", "versionType": "git", "lessThan": "0ce1bc9e46ecabe84772bb561e373c0d9876d6f2" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "5.3", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "5.3" }, { "version": "5.10.258", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.209", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.175", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.142", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.92", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.34", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.0.11", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.0.*" }, { "version": "7.1", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }