Advice Request Is the thunderbird PDF reader secure?

Please provide comments and solutions that are helpful to the author of this topic.


Staff Member
Malware Hunter
Jul 27, 2015
Not too hard to find, but PDF.js ( same viewer that's used by default in Firefox ) was integrated in Thunderbird version 91 released August 2021, and wow that's a pretty busy bee of developers on Github. (y):coffee:

Simply keeping Thunderbird updated, I have a hard time see where this actually could be dangerous enough and extra since I personal as a malware hunter very rarely stumbles over actual alive and still kicking in the wild genuine malicious pdf samples. The majority of those are phishing attacks. Phishing links normally have a very short time span where they are still active. Even a CVE search gives very little info:
but click around too much anywhere on pdf files, is bound to ask for trouble no matter what OS, browser, software etc as it's delusional at best claim something is 100% bulletproof/secure.


Level 21
Thread author
Nov 15, 2017
I was looking around a bit and it can run javascript if it is the same reader as Firefox. I don't know if this can be dangerous or not. The point is that I always open pdfs from very secure sources so I guess there are no problems. Thank you all very much.
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ForgottenSeer 94943

I cannot comment on its security, but I prefer using a dedicated PDF reader, Wonderahare PDFelement in my case.

I don't download PDFs from unknown sources.
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