Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.spnego descriptions cifs.spnego key descriptions contain authority-bearing fields such as pid, uid, creduid, and upcall_target that cifs.upcall treats as kernel-originating inputs. However, userspace can also create keys of this type through request_key(2) or add_key(2), allowing those fields to be supplied without CIFS origin. Only accept cifs.spnego descriptions while CIFS is using its private spnego_cred to request the key.
Affected products
linux: linux kernel
References10
- git.kernel.org/stable/c/0aece6685fc80a8de492688ca2315fb86ec379c7 Patch
- git.kernel.org/stable/c/2035acfb17221729b1b8ac335e941868a04ca079 Patch
- git.kernel.org/stable/c/3da1fdf4efbc490041eb4f836bf596201203f8f2 Patch
- git.kernel.org/stable/c/7713bd320ed4fc3d08a227cd8e41242219a16981 Patch
- git.kernel.org/stable/c/91f89c1d83e80417629791fcef6af8140d7d01c8 Patch
- git.kernel.org/stable/c/9544559e59438a4b609b2fdfa0763d8360572824 Patch
- git.kernel.org/stable/c/a3bbda6502a9398b816fa2e71c9a3f955f58013d Patch
- git.kernel.org/stable/c/cf20038657d6d4974349556a34e08fe0490bebbc Patch
- www.openwall.com/lists/oss-security/2026/06/01/6 Mailing ListThird Party Advisory
- access.redhat.com/errata/RHSA-2026:23258
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 36 · as of 15 November 2026
- CWE
- CWE-20CWE-825
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