Bug 2516396 (CVE-2026-72318) - CVE-2026-72318 kernel: cifs: validate DFS referral string offsets
Summary: CVE-2026-72318 kernel: cifs: validate DFS referral string offsets
Keywords:
Status: NEW
Alias: CVE-2026-72318
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-15 06:10 UTC by OSIDB Bzimport
Modified: 2026-10-15 08:59 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-2026:81406 0 None None None 2026-10-12 18:51:05 UTC
Red Hat Product Errata RHSA-2026:81552 0 None None None 2026-10-12 23:06:55 UTC
Red Hat Product Errata RHSA-2026:82807 0 None None None 2026-10-14 08:51:24 UTC

Description OSIDB Bzimport 2026-08-15 06:10:17 UTC
In the Linux kernel, the following vulnerability has been resolved:

cifs: validate DFS referral string offsets

parse_dfs_referrals() validates that the response header and referral
array fit in the received buffer, but each referral also contains string
offsets supplied by the server.

Those offsets are used to compute the DfsPath and NetworkAddress string
pointers without checking whether they still point inside the response
buffer. A malformed referral can therefore make the computed pointer
exceed the end of the buffer. The resulting negative max_len is then
passed to cifs_strndup_from_utf16(), and the non-Unicode path forwards it
to kstrndup() as a size_t, allowing strnlen() to read out of bounds.

Validate each string offset before deriving the string pointer.

Comment 6 Jon Orris 2026-10-12 18:51:04 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:81406 https://access.redhat.com/errata/RHSA-2026:81406

Comment 7 Jon Orris 2026-10-12 23:06:54 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:81552 https://access.redhat.com/errata/RHSA-2026:81552

Comment 8 Jon Orris 2026-10-14 08:51:23 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:82807 https://access.redhat.com/errata/RHSA-2026:82807


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