UBUNTU-CVE-2026-89716: Medium severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: zram: validate deflate params We must validate user-supplied deflate winbits before we pass it to zlibdeflateworkspacesize(), which triggers BUGON() if winbits value is outside of valid ranges.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42~24.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1~24.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-42.42 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1016.17 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1016.18 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1015.16 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1 - Compensating control
Validate user-supplied deflate winbits values against zlib's valid ranges before passing them to zlib_deflate_workspacesize(), preventing BUG_ON() for out-of-range values.
Event History
Frequently Asked Questions
What condition is required to trigger the kernel failure?
An attacker or local user must be able to supply a deflate winbits value to zram that is outside zlib's valid range. The invalid value reaches zlib_deflate_workspacesize(), which triggers a BUG_ON().
Which Ubuntu kernel package variants are listed as affected?
The listed variants are ubuntu/linux-riscv, ubuntu/linux-realtime, ubuntu/linux-hwe-edge, ubuntu/linux-azure, ubuntu/linux-gcp, ubuntu/linux-azure-fde, ubuntu/linux-gke, and ubuntu/linux-aws-5.0.
What is the impact described by the available information?
The available description identifies a kernel BUG_ON() caused by invalid user-supplied deflate parameters. It does not provide further details about privileges, remote reachability, or impacts beyond that failure condition.