Answer in brief
CVE-2026-64268 records a Unknown severity vulnerability in RDMA/siw: bound Read Response placement to the RREAD length. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-64268 records a Unknown severity vulnerability in RDMA/siw: bound Read Response placement to the RREAD length. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <a31b6d18ded3cc32d9ee85a6ff0726d4274887b2 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <595e6537ad1a210da32cbb9a7f91aa73090915ba || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <b2e26c955f8dd7e8d3f16c858db05245ea4fa817 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <6bc89f34a4597f9f6d41f7a60c67a3153bfe8851 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <423a78ff7928c2601013f73ec6d896f5597d0df5 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <75c93cd3c421890f49ea93f0b978b9b7bb10e5e3 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <7d29f7e9dbd844cae4d3e559cf78324b9642fd6b | a31b6d18ded3cc32d9ee85a6ff0726d4274887b2, 595e6537ad1a210da32cbb9a7f91aa73090915ba, 3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf, b2e26c955f8dd7e8d3f16c858db05245ea4fa817, 6bc89f34a4597f9f6d41f7a60c67a3153bfe8851, 423a78ff7928c2601013f73ec6d896f5597d0df5, 75c93cd3c421890f49ea93f0b978b9b7bb10e5e3, 7d29f7e9dbd844cae4d3e559cf78324b9642fd6b |
| Linux/Linuxgeneric | 5.3 | Not reported |
Published upstream
Jul 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: bound Read Response placement to the RREAD length In drivers/infiniband/sw/siw/siw_qp_rx.c, siw_proc_rresp() places each inbound Read Response DDP segment at sge->laddr + wqe->processed and then accumulates wqe->processed, but it never checks the running total against the sink buffer length on continuation segments. siw_check_sge() resolves and validates the sink memory only on the first fragment (the if (!*mem) branch), and siw_rresp_check_ntoh() compares the cumulative length against wqe->bytes only on the final segment (the !frx->more_ddp_segs guard). A connected siw peer that answers an outstanding RREAD with Read Response segments that keep the DDP Last flag clear, carrying more total payload than the RREAD requested, drives wqe->processed past the validated sink buffer; the next siw_rx_data() call writes out of bounds at sge->laddr + wqe->processed. siw runs iWARP over ordinary routable TCP, so the peer is the remote end of an established RDMA connection and needs no local privilege. Bound every segment before placement, exactly as siw_proc_send() and siw_proc_write() already do for their tagged and untagged paths, and terminate the connection with a base-or-bounds DDP error when the Read Response would overrun the sink buffer. This is the second receive-path length fix for this file. A separate change rejects an MPA FPDU length that underflows the per-fragment remainder in the header decode; that guard does not cover this case, because here each individual segment length is self-consistent and only the accumulated placement offset overruns the buffer.
Quoted source text, attributed separately from HOL analysis.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <a31b6d18ded3cc32d9ee85a6ff0726d4274887b2 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <595e6537ad1a210da32cbb9a7f91aa73090915ba || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <b2e26c955f8dd7e8d3f16c858db05245ea4fa817 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <6bc89f34a4597f9f6d41f7a60c67a3153bfe8851 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <423a78ff7928c2601013f73ec6d896f5597d0df5 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <75c93cd3c421890f49ea93f0b978b9b7bb10e5e3 || >=8b6a361b8c482f22ac99c3273285ff16b23fba91 <7d29f7e9dbd844cae4d3e559cf78324b9642fd6b | a31b6d18ded3cc32d9ee85a6ff0726d4274887b2, 595e6537ad1a210da32cbb9a7f91aa73090915ba, 3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf, b2e26c955f8dd7e8d3f16c858db05245ea4fa817, 6bc89f34a4597f9f6d41f7a60c67a3153bfe8851, 423a78ff7928c2601013f73ec6d896f5597d0df5, 75c93cd3c421890f49ea93f0b978b9b7bb10e5e3, 7d29f7e9dbd844cae4d3e559cf78324b9642fd6b |
| Linux/Linuxgeneric | 5.3 | Not reported |
Published upstream
Jul 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: bound Read Response placement to the RREAD length In drivers/infiniband/sw/siw/siw_qp_rx.c, siw_proc_rresp() places each inbound Read Response DDP segment at sge->laddr + wqe->processed and then accumulates wqe->processed, but it never checks the running total against the sink buffer length on continuation segments. siw_check_sge() resolves and validates the sink memory only on the first fragment (the if (!*mem) branch), and siw_rresp_check_ntoh() compares the cumulative length against wqe->bytes only on the final segment (the !frx->more_ddp_segs guard). A connected siw peer that answers an outstanding RREAD with Read Response segments that keep the DDP Last flag clear, carrying more total payload than the RREAD requested, drives wqe->processed past the validated sink buffer; the next siw_rx_data() call writes out of bounds at sge->laddr + wqe->processed. siw runs iWARP over ordinary routable TCP, so the peer is the remote end of an established RDMA connection and needs no local privilege. Bound every segment before placement, exactly as siw_proc_send() and siw_proc_write() already do for their tagged and untagged paths, and terminate the connection with a base-or-bounds DDP error when the Read Response would overrun the sink buffer. This is the second receive-path length fix for this file. A separate change rejects an MPA FPDU length that underflows the per-fragment remainder in the header decode; that guard does not cover this case, because here each individual segment length is self-consistent and only the accumulated placement offset overruns the buffer.
Quoted source text, attributed separately from HOL analysis.