Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
perf: Revert to requiring CAP_SYS_ADMIN for uprobes
Jann reports that uprobes can be used destructively when used in the middle of an instruction. The kernel only verifies there is a valid instruction at the requested offset, but due to variable instruction length cannot determine if this is an instruction as seen by the intended execution stream.
Additionally, Mark Rutland notes that on architectures that mix data in the text segment (like arm64), a similar things can be done if the data word is ‘mistaken’ for an instruction.
As such, require CAP_SYS_ADMIN for uprobes.
Details
- Affected product:
- AlmaLinux 9.2 ESU , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+1 more)
In the Linux kernel, the following vulnerability has been resolved:
perf: Revert to requiring CAP_SYS_ADMIN for uprobes
Jann reports that uprobes can be used destructively when used in the middle of an instruction. The kernel only verifies there is a valid instruction at the requested offset, but due to variable instruction length cannot determine if this is an instruction as seen by the intended execution stream.
Additionally, Mark Rutland notes that on architectures that mix data in the text segment (like arm64), a similar things can be done if the data word is ‘mistaken’ for an instruction.
As such, require CAP_SYS_ADMIN for uprobes.