Aug 06, 2021 11:15:00

Microsoft tests 'Super Duper Secure Mode' that enables secure browsing by disabling JIT in Edge

One of the security issues in web browsers is related to the

Javascript engine, which includes the technology 'Just-in-time compiler (JIT compiler)' for accelerating specific tasks of Javascript. To address this, Microsoft has added a 'Super Duper Secure Mode' that disables JIT to Edge's Canary, Dev, and Beta channels.

Super Duper Secure Mode | Microsoft Browser Vulnerability Research
https://microsoftedge.github.io/edgevr/posts/Super-Duper-Secure-Mode/

According to Microsoft's vulnerability research team, the most common attacks on web browsers that exploit vulnerabilities are exploiting bugs around the Javascript engine. If you know that you are being targeted, it seems that you can take measures, but for example, like the acceleration technology 'JIT compiler', although the performance is improved, the process is complicated, so the final cost in terms of security There seems to be a case where you are supposed to pay. Of the Common Vulnerabilities and Exposures (CVEs) granted after 2019, about 45% of CVEs targeting

the V8 Javascript engine were JIT-related.

The Microsoft vulnerability research team hypothesized that 'generally users want high speed, so developers enable JIT as a matter of course even if it costs security, but what if they simply disable it?' Has come to the conclusion that by halving the number of bugs that need to be fixed in the first place, the area targeted for attack will decrease, making the attack itself difficult.

On the other hand, from the user's point of view, by reducing the frequency of security updates, it is possible to reduce the 'test to see if there are any problems with updates' that occur especially in large companies, and the performance degradation is at a level where there is almost no impact. I understand. The graph below shows the results of hundreds of tests with JIT disabled, with green representing improvement, yellow representing no change, and red representing deterioration.

In the survey, although there was a result that the score decreased by 58% in the Javascript benchmark, it does not mean that 'performance decreases by 58%', so 'users often do not notice the effect'.

Based on these results, Microsoft decided to test the 'Super Duper Secure Mode' with JIT disabled and Intel-provided attack mitigation technology

CET enabled. If you access 'edge: // flags' in Edge Canary, Edge Dev, Edge Beta, the item 'Super Duper Secure Mode' has already been added. To enable it, you need to change it from 'Default' to 'Enabled'.

Microsodt will continue to test over the next few months to find a way to balance speed and safety.