Bug 2507089 (CVE-2026-64268) - CVE-2026-64268 kernel: Kernel: Remote out-of-bounds write in RDMA/siw
Summary: CVE-2026-64268 kernel: Kernel: Remote out-of-bounds write in RDMA/siw
Keywords:
Status: NEW
Alias: CVE-2026-64268
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-07-25 10:04 UTC by OSIDB Bzimport
Modified: 2026-09-23 01:39 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:63013 0 None None None 2026-09-03 04:02:10 UTC
Red Hat Product Errata RHSA-2026:63014 0 None None None 2026-09-03 04:16:24 UTC
Red Hat Product Errata RHSA-2026:63129 0 None None None 2026-09-04 00:53:06 UTC
Red Hat Product Errata RHSA-2026:65710 0 None None None 2026-09-09 00:35:52 UTC
Red Hat Product Errata RHSA-2026:67720 0 None None None 2026-09-16 00:55:07 UTC
Red Hat Product Errata RHSA-2026:68100 0 None None None 2026-09-16 14:07:46 UTC
Red Hat Product Errata RHSA-2026:69837 0 None None None 2026-09-22 03:33:46 UTC
Red Hat Product Errata RHSA-2026:69906 0 None None None 2026-09-22 08:28:21 UTC
Red Hat Product Errata RHSA-2026:70482 0 None None None 2026-09-23 01:39:22 UTC
Red Hat Product Errata RHSA-2026:70483 0 None None None 2026-09-23 00:24:58 UTC

Description OSIDB Bzimport 2026-07-25 10:04:26 UTC
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.

Comment 1 Mauro Matteo Cascella 2026-07-29 17:27:32 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026072559-CVE-2026-64268-629a@gregkh/T

Comment 5 errata-xmlrpc 2026-09-03 04:02:09 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:63013 https://access.redhat.com/errata/RHSA-2026:63013

Comment 6 errata-xmlrpc 2026-09-03 04:16:23 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:63014 https://access.redhat.com/errata/RHSA-2026:63014

Comment 7 errata-xmlrpc 2026-09-04 00:53:05 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:63129 https://access.redhat.com/errata/RHSA-2026:63129

Comment 8 errata-xmlrpc 2026-09-09 00:35:51 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Via RHSA-2026:65710 https://access.redhat.com/errata/RHSA-2026:65710

Comment 9 Jon Orris 2026-09-16 00:55:07 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:67720 https://access.redhat.com/errata/RHSA-2026:67720

Comment 10 Jon Orris 2026-09-16 14:07:46 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:68100 https://access.redhat.com/errata/RHSA-2026:68100

Comment 11 Jon Orris 2026-09-22 03:33:45 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:69837 https://access.redhat.com/errata/RHSA-2026:69837

Comment 12 Jon Orris 2026-09-22 08:28:20 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Via RHSA-2026:69906 https://access.redhat.com/errata/RHSA-2026:69906

Comment 13 Jon Orris 2026-09-23 00:24:57 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:70483 https://access.redhat.com/errata/RHSA-2026:70483

Comment 14 Jon Orris 2026-09-23 01:39:21 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:70482 https://access.redhat.com/errata/RHSA-2026:70482


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