CVE-2026-46243
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.
- Published Jun 1, 2026
- CVSS 7.1 high
- 0.2% chance of exploitation in the next 30 days (EPSS)
- A fix is available
Affected software
In the news
- Multiple vulnerabilities in the Ubuntu Linux kernel CERT-FR ·
- Multiple vulnerabilities in the Ubuntu Linux kernel CERT-FR ·
- CIFS Upcall Privilege Escalation - Linux Kernel - "CIFSwitch" Red Hat Security Bulletins ·