SB2026091929 - Out-of-bounds read in Linux kernel mailbox driver
Published: September 19, 2026
Security Bulletin ID
SB2026091929
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Out-of-bounds read (CVE-ID: CVE-2026-90191)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in the riscv-sbi-mpxy mailbox RPMI notification handler when processing SBI-returned notification data. A local user can trigger processing of malformed RPMI notification data to disclose sensitive information.
Remediation
Install update from vendor's website.