Linux Kernel up to 7.1.3 siw siw_qp_rx.c siw_proc_rresp processed/laddr out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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9.5$0-$5k4.66-

Summaryinfo

A vulnerability has been found in Linux Kernel up to 7.1.3 and classified as very critical. This issue affects the function siw_proc_rresp of the file drivers/infiniband/sw/siw/siw_qp_rx.c of the component siw. The manipulation of the argument processed/laddr leads to out-of-bounds. This vulnerability is uniquely identified as CVE-2026-64268. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.1.3. It has been rated as very critical. This issue affects the function siw_proc_rresp of the file drivers/infiniband/sw/siw/siw_qp_rx.c of the component siw. The manipulation of the argument processed/laddr with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-64268 since 07/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/25/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4 or 7.2-rc1 eliminates this vulnerability. Applying the patch a31b6d18ded3cc32d9ee85a6ff0726d4274887b2/595e6537ad1a210da32cbb9a7f91aa73090915ba/3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf/b2e26c955f8dd7e8d3f16c858db05245ea4fa817/6bc89f34a4597f9f6d41f7a60c67a3153bfe8851/423a78ff7928c2601013f73ec6d896f5597d0df5/75c93cd3c421890f49ea93f0b978b9b7bb10e5e3/7d29f7e9dbd844cae4d3e559cf78324b9642fd6b is able to eliminate this problem.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.261/5.15.212/6.1.178/6.6.145/6.12.96/6.18.39/7.1.4/7.2-rc1
Patch: a31b6d18ded3cc32d9ee85a6ff0726d4274887b2/595e6537ad1a210da32cbb9a7f91aa73090915ba/3ef7e052cbd05a8b13a51a07b185a39ec93ee1cf/b2e26c955f8dd7e8d3f16c858db05245ea4fa817/6bc89f34a4597f9f6d41f7a60c67a3153bfe8851/423a78ff7928c2601013f73ec6d896f5597d0df5/75c93cd3c421890f49ea93f0b978b9b7bb10e5e3/7d29f7e9dbd844cae4d3e559cf78324b9642fd6b

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64268 (🔒)
GCVE (CVE): GCVE-0-2026-64268
GCVE (VulDB): GCVE-100-383057

Entryinfo

Created: 07/25/2026 12:19
Changes: 07/25/2026 12:19 (61)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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