PT-2023-2348 · Linux+9 · Linux Kernel+9
Es0J
+2
·
Published
2023-02-27
·
Updated
2024-11-21
·
CVE-2023-1998
CVSS v3.1
5.6
Medium
| Vector | AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N |
Name of the Vulnerable Software and Affected Versions
Linux kernel version 6.2
Description
The Linux kernel allows userspace processes to enable mitigations by calling prctl with PR SET SPECULATION CTRL, which disables the speculation feature as well as by using seccomp. However, on VMs of at least one major cloud provider, the kernel still left the victim process exposed to attacks in some cases even after enabling the spectre-BTI mitigation with prctl. This happened because when plain IBRS was enabled, the kernel had some logic that determined that STIBP was not needed. The IBRS bit implicitly protects against cross-thread branch target injection. However, with legacy IBRS, the IBRS bit was cleared on returning to userspace, due to performance reasons, which disabled the implicit STIBP and left userspace threads vulnerable to cross-thread branch target injection against which STIBP protects.
Recommendations
At the moment, there is no information about a newer version that contains a fix for this vulnerability.
Exploit
Side Channel Attack
Found an issue in the description? Have something to add? Feel free to write us 👾
Related Identifiers
Affected Products
Alt Linux
Almalinux
Astra Linux
Centos
Linuxmint
Linux Kernel
Red Hat
Rocky Linux
Suse
Ubuntu