Use of uninitialized resource in Linux kernel - CVE-2026-46139
Published: May 29, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to uninitialized memory in build_sec_desc() when building an ACL descriptor. A local user can trigger construction of a security descriptor with a non-zero reserved field to cause a denial of service.
The issue can cause chmod to fail with EINVAL when the malformed security descriptor is rejected.
Affected software
Ubuntu
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
How to mitigate CVE-2026-46139
linux (Ubuntu package) - addressed in versions 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2, 7.0.0-28.28, 7.0.0-28.28.1, 7.0.0-1003.4, 7.0.0-1008.8
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1, 7.0.0-1008.8, 7.0.0-1010.10
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-aws (Ubuntu package) - addressed in versions 6.8.0-1061.64+1, 7.0.0-1009.9, 7.0.0-1015.15
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1, 7.0.0-1009.9, 7.0.0-1010.10
linux-azure-fips (Ubuntu package) - update to 6.8.0-1063.71+fips2
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1009.9
External References
- https://git.kernel.org/stable/c/4c3ed344a970aad51388ac3b0145b98318f0e21f
- https://git.kernel.org/stable/c/5e489c6c47a2ac15edbaca153b9348e42c1eacab
- https://git.kernel.org/stable/c/941a1e6eb35440336913afc88a82103291956d5d
- https://git.kernel.org/stable/c/9bdb2ca31368b7671949dfb94a5d57ffccd01edd
- https://git.kernel.org/stable/c/be1ef9512a3f5a755895c24f31b334342f4aa15b
Related Security Bulletins
- Use of uninitialized resource in Linux kernel smb client
- Ubuntu update for linux-oem-7.0
- Ubuntu update for linux
- Ubuntu update for linux
- Ubuntu update for linux-gcp-fips
- Ubuntu update for linux-oracle-6.8
- Ubuntu update for linux-fips
- Ubuntu update for linux-ibm
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure-fde-6.8
- Ubuntu update for linux-azure-fips
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-aws
- Ubuntu update for linux-hwe-6.8
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-ibm
- Ubuntu update for linux-aws