CVE-2026-46333

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

ptrace: slightly saner ‘get_dumpable()’ logic

The ‘dumpability’ of a task is fundamentally about the memory image of the task - the concept comes from whether it can core dump or not - and makes no sense when you don’t have an associated mm.

And almost all users do in fact use it only for the case where the task has a mm pointer.

But we have one odd special case: ptrace_may_access() uses ‘dumpable’ to check various other things entirely independently of the MM (typically explicitly using flags like PTRACE_MODE_READ_FSCREDS). Including for threads that no longer have a VM (and maybe never did, like most kernel threads).

It’s not what this flag was designed for, but it is what it is.

The ptrace code does check that the uid/gid matches, so you do have to be uid-0 to see kernel thread details, but this means that the traditional “drop capabilities” model doesn’t make any difference for this all.

Make it all make a bit more sense by saying that if you don’t have a MM pointer, we’ll use a cached “last dumpability” flag if the thread ever had a MM (it will be zero for kernel threads since it is never set), and require a proper CAP_SYS_PTRACE capability to override.

Affected product:

AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

kernel @ 3.10.0 (+15 more)

Live-patch status from KernelCare for each operating system.