this post was submitted on 10 Aug 2024
49 points (90.2% liked)

Cybersecurity

5677 readers
114 users here now

c/cybersecurity is a community centered on the cybersecurity and information security profession. You can come here to discuss news, post something interesting, or just chat with others.

THE RULES

Instance Rules

Community Rules

If you ask someone to hack your "friends" socials you're just going to get banned so don't do that.

Learn about hacking

Hack the Box

Try Hack Me

Pico Capture the flag

Other security-related communities [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected]

Notable mention to [email protected]

founded 1 year ago
MODERATORS
 

AMD is warning about a high-severity CPU vulnerability named SinkClose that impacts multiple generations of its EPYC, Ryzen, and Threadripper processors. The vulnerability allows attackers with Kernel-level (Ring 0) privileges to gain Ring -2 privileges and install malware that becomes nearly undetectable.

Tracked as CVE-2023-31315 and rated of high severity (CVSS score: 7.5), the flaw was discovered by IOActive Enrique Nissim and Krzysztof Okupski, who named privilege elevation attack 'Sinkclose.'

Full details about the attack will be presented by the researchers at tomorrow in a DefCon talk titled "AMD Sinkclose: Universal Ring-2 Privilege Escalation."

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 2 points 3 months ago (1 children)

Maybe we could use this to disable the Intel ME equivalent for AMD on those generations.

[–] [email protected] 1 points 3 months ago (1 children)

PSP is required for x86 core initialisation.

[–] [email protected] 1 points 3 months ago (1 children)

But if you can get around the signing requirements, it would be trivial to make the psp firmware only do that. (Probably not trivial, but at least technically feasable)

[–] [email protected] 3 points 3 months ago* (last edited 3 months ago)

I did want to expand on this, I'd be curious as to what Jeremy Soller found getting certain Ryzen mobile platforms working with coreboot.

Perhaps we'll need to wait for OpenSIL for more comprehensive support.

Aside from x86 core init, PSP is still required for specific OS security requirements. Can at least take solace in the fact that OEMs seem to have completely turned down MS Pluton.