Out-of-bounds read in Linux kernel - CVE-2026-45999
Published: May 28, 2026
Vulnerability details
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in z_erofs_lz4_handle_overlap() when processing a crafted EROFS image during LZ4 inplace decompression. A local user can mount a crafted image and trigger decompression to disclose sensitive information.
The issue occurs for illegal extents where partial decoding is disabled and m_llen is smaller than m_plen, causing an unsigned underflow in the outpages minus inpages calculation.
Affected software
Ubuntu
openEuler
perf-debuginfo
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-source
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
python3-perf
python3-perf-debuginfo
kernel-extra-modules
linux (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-fips (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-aws (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
How to mitigate CVE-2026-45999
perf-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
bpftool - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
bpftool-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-debugsource - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-devel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-headers - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-source - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-tools - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-tools-devel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
perf - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
python3-perf - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
python3-perf-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.14.145
kernel-extra-modules - update to 6.6.0-145.3.14.145
linux (Ubuntu package) - addressed in versions 5.15.0-195.205~20.04.1, 5.15.0-195.205, 5.15.0-198.208~20.04.1, 5.15.0-198.208+fips1, 5.15.0-1080.84, 5.15.0-1100.108, 5.15.0-1109.111, 5.15.0-1109.114, 5.15.0-1111.115~20.04.1, 5.15.0-1111.115, 5.15.0-1112.118~20.04.1, 5.15.0-1112.118, 5.15.0-1113.119, 5.15.0-1114.120, 5.15.0-1116.125~20.04.1, 5.15.0-1117.124~20.04.1, 5.15.0-1117.124, 5.15.0-1117.124+fips1, 5.15.0-1122.131~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1123.132, 5.15.0-1123.132+fips1, 5.15.0.195.160, 5.15.0.195.205~20.04.1, 5.15.0.198.114, 5.15.0.198.171, 5.15.0.198.208~20.04.1, 5.15.0.1080.83~20.04.1, 5.15.0.1100.99, 5.15.0.1109.105, 5.15.0.1109.113, 5.15.0.1111.108, 5.15.0.1111.115~20.04.1, 5.15.0.1112.111, 5.15.0.1112.118~20.04.1, 5.15.0.1113.112, 5.15.0.1114.110, 5.15.0.1116.120, 5.15.0.1117.113, 5.15.0.1117.120, 5.15.0.1117.124~20.04.1, 5.15.0.1122.131~20.04.1, 5.15.0.1123.107, 5.15.0.1123.121, 5.15.0.1123.132~20.04.1, 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72~22.04.1, 6.8.0-1064.72, 6.8.1-1056.57~22.04.2, 6.8.1-1056.57, 7.0.0-27.27
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112, 6.8.0-1059.62~22.04.1, 6.8.0-1059.62, 6.8.0-1059.62.1, 7.0.0-1013.13
linux-oracle-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.120~20.04.1, 5.15.0.1114.120~20.04.1
linux-gcp-5.15 (Ubuntu package) - addressed in versions 5.15.0-1118.128~20.04.1, 5.15.0.1118.128~20.04.1
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1118.128, 5.15.0-1118.128+fips1, 5.15.0.1118.107, 5.15.0.1118.115
linux-azure-fde (Ubuntu package) - addressed in versions 5.15.0-1122.131, 5.15.0.1122.131, 6.8.0-1062.69
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2~22.04.1, 6.8.0-136.136.2, 6.8.0-1058.61
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62~22.04.1, 6.8.0-1061.62
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64~22.04.1, 6.8.0-1061.64+fips1
linux-aws (Ubuntu package) - update to 6.8.0-1061.64+1
linux-raspi (Ubuntu package) - addressed in versions 6.8.0-1061.65, 6.8.0-2050.52, 7.0.0-1014.14
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71~22.04.1, 6.8.0-1063.71, 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
External References
- https://git.kernel.org/stable/c/21e161de2dc660b1bb70ef5b156ab8e6e1cca3ab
- https://git.kernel.org/stable/c/43a878639b90e9721ffa5eb616a7e6d8454adef3
- https://git.kernel.org/stable/c/bbbbb3f0d7864238a8da2a94cd6ec013fee06a2e
- https://git.kernel.org/stable/c/c9ce18e6bb2c467ec85756dc7989b547b7584fee
- https://git.kernel.org/stable/c/f1374fa6e57fd836623668d782ded9244cfd2938
Related Security Bulletins
- Out-of-bounds read in Linux kernel erofs
- openEuler 24.03 LTS SP3 update for kernel
- Ubuntu update for linux
- Ubuntu update for linux-raspi
- Ubuntu update for linux-nvidia
- 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-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
- openEuler 24.03 LTS SP1 update for kernel
- Ubuntu update for linux-hwe-6.8
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-ibm
- Ubuntu update for linux-raspi
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-gcp
- Ubuntu update for linux-gcp-5.15
- Ubuntu update for linux-oracle-5.15
- Ubuntu update for linux