Re: CVE request: uglify-js node.js module <2.4.24 incorrectly handles non-boolean comparisons during minification

[Florian Weimer <fweimer () redhat com>]

On 08/24/2015 08:26 PM, Reed Loden wrote:
> As seen on Hacker News -- https://zyan.scripts.mit.edu/blog/backdooring-js/
>
> Blog post has all the details, but basically the UglifyJS node module has a
> problem where the combination of De Morgan’s Law and non-boolean values can
> lead to a case where code is incorrectly minified, which can lead to
> possibly malicious minified JS code.
>
> UglifyJS is a "JavaScript parser / mangler / compressor / beautifier
> toolkit" for Node.js.

How is this different from a any other compiler bug?  They can be abused
in similar ways by crafted code, and we don't treat them as
vulnerabilities (unless there is actual application impact beyond
synthetic test cases).

Note that I'm not saying this isn't a nice find, I'm just not sure if it
should be considered as a security by itself.

-- 
Florian Weimer / Red Hat Product Security