SB2026081902 - Red Hat Enterprise Linux 9 update for kernel
Published: August 19, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Improper input validation (CVE-ID: CVE-2026-31411)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper input validation in sigd_send() when handling sendmsg() input containing a forged vcc pointer. A local user can send a specially crafted message to cause a denial of service.
Exploitation requires control of the ATM signaling daemon role via the ATMSIGD_CTRL ioctl.
2) Out-of-bounds read (CVE-ID: CVE-2026-43112)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to out-of-bounds read in cifs_sanitize_prepath when parsing path strings containing only delimiters or no path content. A local user can supply a crafted path string to cause a denial of service.
The issue can be triggered by an empty string or a string such as "/".
3) Improper privilege management (CVE-ID: CVE-2025-54518)
CWE-ID: CWE-269 - Improper Privilege Management
CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to escalate privileges.
The vulnerability exists due to improper privilege management in x86 CPU opcode cache handling when executing code on affected AMD Fam17h CPUs. A local user can execute code to escalate privileges.
The issue can permit escalation across privilege boundaries including userspace to kernel and guest to host, and only AMD Fam17h CPUs based on the Zen2 microarchitecture are believed to be affected.
Remediation
Install update from vendor's website.