CVE-2026-53282

Summary

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

x86/kexec: Push kjump return address even for non-kjump kexec

The version of purgatory code shipped by kexec-tools attempts to look above the top of its stack to find a return address for a kjump, even in a non-kjump kexec.

After the commit in Fixes: the word above the stack might not be there, leading to a fault (which is at least now caught by my exception-handling code in kexec).

That commit fixed things for the actual kjump path, but no longer "gratuitously" pushes the unused return address to the stack in the non-kjump path. Put that back in the non-kjump path, to prevent purgatory from crashing when trying to access it.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux2cacf7f23a024ab1fdc603ca6a4f4c8b2de9f64e < b0bd7a850e1f082560959707dbf57b0402071646affected
LinuxLinux2cacf7f23a024ab1fdc603ca6a4f4c8b2de9f64e < 7dba9631faa2ee0785e8c2bf0e3d90a05f26dd8caffected
LinuxLinux2cacf7f23a024ab1fdc603ca6a4f4c8b2de9f64e < 786a45757dcdf8f2beb9d4a6db605db16c18b2b4affected
LinuxLinux6.14affected
LinuxLinux0 < 6.14unaffected
LinuxLinux6.18.33 <= 6.18.*unaffected
LinuxLinux7.0.10 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References