Mitigations against the infamous Spectre attacks are now in ruins and billions of systems around the world are once again vulnerable to the kernel-level problem. According to research from a team from the University of California (San Diego) and University of Virginia, all modern Intel and AMD chips with micro-op caches have the vulnerability.

However, chip giant Intel suggests the research is incorrect and its current security protection does prevent fresh Spectre attacks.

In the paper, the researchers show how new Spectre attacks break through defenses put in place back in 2018 when the vulnerabilities first emerged. As with the original outbreak of the problem, all Intel chips manufactured over the last decade are included.


Researchers dub the vulnerability a Spectre flaw because it has many of the same properties, including being built directly into processors. Because of this new finding, all defenses for the previous Spectre are useless.

The new attack method involves targeting the micro-op cache, which is a built-in structure on a CPU that helps boost performance by permanently storing core commands. Processors can call on these commands more quickly. However, the new exploit sends the commands down the wrong path, and while the processor reacts and goes back, it cannot do so quick enough.

If successfully exploited, attackers would be able to access systems, including personal files.

It’s Back

Meltdown and Spectre were kernel level flaws in Intel and other chips first found in 2018. Crossing generations and platforms, the vulnerabilities affected most devices and took months to fix. Widely seen as one of the most dangerous computing flaws ever, Spectre was thought to be a wake up call to the cyber community.

Since that first outbreak and the three years since, security researchers have been working hard to prevent Spectre and fix flaws. All that work has been demolished because the defenses already in place only protect later stage of the process.

While generating attacks would be difficult for threat actors, it would not be impossible. ThreatPost reached out to Intel and received the following response from the company:

“Intel reviewed the report and informed researchers that existing mitigations were not being bypassed and that this scenario is addressed in our secure coding guidance. Software following our guidance already have protections against incidental channels including the uop cache incidental channel. No new mitigations or guidance are needed.”

In other words, Intel refutes the research and insists current defenses do protect against new Spectre attacks. UVA Engineering Assistant Professor of Computer Science Ashish Venkat says the vulnerability the research team found is different:

“Certainly, we agree that software needs to be more secure, and we agree as a community that constant-time programming is an effective means to writing code that is invulnerable to side-channel attacks. However, the vulnerability we uncover is in hardware, and it is important to also design processors that are secure and resilient against these attacks.”

Tip of the day:

Do you often experience PC freezes or crashs with Blue Screens of Death (BSOD)? Then you should use Windows Memory Diagnostic to test your computers RAM for any problems that might be caused from damaged memory modules. This is a tool built into Windows 10 which can be launched at startup to run various memory checks.