CVE-2026-46333: Debian Linux

High severity, CVSS 7.1. EPSS: 0.5% chance of exploitation in the next 30 days.

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 products

• Debian Debian Linux: version 11.0 only
• Linux Linux Kernel: from 3.16.52, before 3.17 (fixed in 3.17); from 4.4.40, before 4.5 (fixed in 4.5); from 4.8.16, before 4.9 (fixed in 4.9); from 4.9.1, before 5.10.256 (fixed in 5.10.256); from 5.11, before 5.15.207 (fixed in 5.15.207); from 5.16, before 6.1.173 (fixed in 6.1.173); …

Published 2026-05-15. Last modified 2026-08-24.