1782186 - Opening an encrypted pdf: the encryption dictionary's `StrF` and `StmF` are swapped

Status: RESOLVED FIXED

(Firefox :: PDF Viewer, defect, P1)

Description

[battlechicken74]

Attachment: egy kor.pdf

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0

Steps to reproduce:

Tried to open a pdf file.

• open attached file
• password is 'Hello'
• observe that the screen is empty

now, if you exchange the 2 variables in the pdf (with notepad++ for example)
/StmF /StdCF -> /StmF /Identity
/StrF /Identity -> /StrF /StdCF
then it works. -- a circle appears as intended
All other pdf reader apps that i tried work. (acrobat, sumatra)

Actual results:

Didn't open

Expected results:

Should have opened

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::PDF Viewer' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Calixte Denizet (:calixte)]

I can reproduce the issue in Firefox nightly on Windows 11.
It works correctly in either Acrobat or Foxit or Preview, but impossible to just open it in Edge.

Comment 3

[Calixte Denizet (:calixte)]

The CipherTransform ctor takes a string cipher ctor and a stream cipher ctor as arguments:
https://github.com/mozilla/pdf.js/blob/0c5afe9269f3f065bd4bdab37bb1322b0587673f/src/core/crypto.js#L1381
but the arguments are swaped when it's called:
https://github.com/mozilla/pdf.js/blob/0c5afe9269f3f065bd4bdab37bb1322b0587673f/src/core/crypto.js#L1860-L1867

Comment 4

[GitHub Bugzilla PR Linker]

Attachment: Link to GitHub pull-request: https://github.com/mozilla/pdf.js/pull/15238