SB2026072903 - Red Hat Enterprise Linux 9 update for kernel-rt
Published: July 29, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Use-after-free (CVE-ID: CVE-2026-31488)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 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/E:U/U:Clear
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in the amdgpu display manager stream handling logic when processing KMS commits involving DSC validation and unrelated mode changes. A local user can trigger a crafted display configuration change to cause a denial of service.
The issue can occur when MST/DSC configuration changes happen in the same commit as a separate mode change, leading to incorrect stream lifetime handling when the stream is later disabled.
2) Out-of-bounds read (CVE-ID: CVE-2026-31684)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an out-of-bounds read in tcf_csum_act() when processing packets with nested in-payload VLAN headers. A remote attacker can send a specially crafted packet to cause a denial of service.
3) Use-after-free (CVE-ID: CVE-2026-46116)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 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/E:U/U:Clear
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in __xfrm_state_delete when deleting xfrm_state list entries during xfrm_state lifecycle handling. A local user can trigger repeated deletion of the same xfrm_state object to cause a denial of service.
The issue was reproduced under syzkaller load during network namespace cleanup in the xfrm subsystem.
4) Integer overflow (CVE-ID: CVE-2026-46209)
CWE-ID: CWE-190 - Integer overflow
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to perform out-of-bounds read or write operations.
The vulnerability exists due to an integer overflow in drm_gem_fb_init_with_funcs() when initializing framebuffer plane dimensions for sub-sampled pixel formats. A local user can create a specially crafted framebuffer configuration to perform out-of-bounds read or write operations.
The issue can occur for certain pixel format and dimension combinations where plane height calculation truncates instead of rounding up, causing the GEM object size check to accept an undersized object.
5) Buffer overflow (CVE-ID: CVE-2025-38085)
CWE-ID: CWE-119 - Memory corruption
CVSSv4: 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/E:U/U:Clear
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to memory corruption within the huge_pmd_unshare() function in mm/hugetlb.c. A local user can perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.