Synopsis
The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.
Description
The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.
- In the Linux kernel, the following vulnerability has been resolved: x86: fix user address masking non- canonical speculation issue It turns out that AMD has a Meltdown Lite(tm) issue with non-canonical accesses in kernel space. And so using just the high bit to decide whether an access is in user space or kernel space ends up with the good old leak speculative data if you have the right gadget using the result: CVE-2020-12965 Transient Execution of Non-Canonical Accesses Now, the kernel surrounds the access with a STAC/CLAC pair, and those instructions end up serializing execution on older Zen architectures, which closes the speculation window. But that was true only up until Zen 5, which renames the AC bit [1]. That improves performance of STAC/CLAC a lot, but also means that the speculation window is now open. Note that this affects not just the new address masking, but also the regular valid_user_address() check used by access_ok(), and the asm version of the sign bit check in the get_user() helpers. It does not affect put_user() or clear_user() variants, since there's no speculative result to be used in a gadget for those operations. (CVE-2024-50102)
Note that Nessus relies on the presence of the package as reported by the vendor.
Solution
There is no known solution at this time.
Plugin Details
File Name: unpatched_CVE_2024_50102.nasl
Agent: unix
Supported Sensors: Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:N/A:N
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched
Exploit Ease: No known exploits are available
Vulnerability Publication Date: 11/5/2024