[R-pkg-devel] Possible malware(?) in a vignette

[Simon Urbanek]

Iñaki,

I think you got it backwards in your conclusions: CRAN has not generated that PDF file (and Windows machines are not even involved here), it is the contents of a contributed package, so CRAN itself is not compromised. Also it is far from clear that it is really a malware - in fact it's certainly NOT what the website you linked claims as those tags imply trojans disguising ZIPped executables as PDF, but the file is an actual valid PDF and not even remotely a ZIP file (in fact is it consistent with pdflatex output). I looked at the decompressed payload of the PDF and the only binary payload are embedded fonts so my guess would be that some byte sequence in the fonts gets detected as false-positive trojan, but since there is no detail on the report we can just guess. False-positives are a common problem and this would not be the first one. Further indication that it's a false-positive is that a simple re-packaging the streams (i.e. NOT changing the actual PDF contents) make the same file pass the tests as clean.

Also note that there is a bit of a confusion as the currently released version (poweRlaw 0.80.0) does not get flagged, so it is only the archived version (from 2020).

Cheers,
Simon



> On 26/01/2024, at 12:02 AM, Iñaki Ucar <iucar using fedoraproject.org> wrote:
> 
> On Thu, 25 Jan 2024 at 10:13, Colin Gillespie <csgillespie using gmail.com> wrote:
>> 
>> Hi All,
>> 
>> I've had two emails from users in the last 24 hours about malware
>> around one of my vignettes. A snippet from the last user is:
>> 
>> ---
>> I was trying to install a R package that depends on PowerRLaw two
>> weeks ago.  However my virus protection software F secure did not
>> allow me to install it from CRAN, while installation from GitHub
>> worked normally. Virus protection software claimed that
>> d_jss_paper.pdf is compromised. I asked about this from our IT support
>> and they asked it from the company F secure. Now F secure has analysed
>> the file and according them it is malware.
>> 
>> “Upon analyzing, our analysis indicates that the file you submitted is
>> malicious. Hence the verdict will remain
> 
> See https://www.virustotal.com/gui/file/9486d99c1c1f2d1b06f0b6c5d27c54d4f6e39d69a91d7fad845f323b0ab88de9/behavior
> 
> According to the sandboxed analysis, there's something there trying to
> tamper with the Acrobat installation. It tries several Windows paths.
> That's not good.
> 
> The good news is that, if I recreate the vignette from your repo, the
> file is different, different hash, and it's clean.
> 
> The bad news is that... this means that CRAN may be compromised. I
> urge CRAN maintainers to check all the PDF vignettes and scan the
> Windows machines for viruses.
> 
> Best,
> Iñaki
> 
> 
>> 
>> ---
>> 
>> Other information is:
>> 
>> * Package in question:
>> https://cran.r-project.org/web/packages/poweRlaw/index.html
>> * Package hasn't been updated for three years
>> * Vignette in question:
>> https://cran.r-project.org/web/packages/poweRlaw/vignettes/d_jss_paper.pdf
>> 
>> CRAN asked me to fix
>> https://cran.r-project.org/web/checks/check_results_poweRlaw.html a
>> couple of days ago - which I'm in the process of doing.
>> 
>> Any ideas?
>> 
>> Thanks
>> Colin
>> 
>> ______________________________________________
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>> https://stat.ethz.ch/mailman/listinfo/r-package-devel
> 
> 
> 
> -- 
> Iñaki Úcar
>