foren/23-719 (#45)

* pdf foren

* ah yes deploying a pdf

* @Blckbrry-Pi

23-719/chall.yaml

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+name: 23-719
+categories:
+  - foren
+value: 50
+flag: bcactf{rEAl_WOrLd_appLIc4t1ons_Of_cTf_ad04cc78601d5da8}
+description: |-
+  that's a nice unanimous supreme court decision you've made public,
+  sure would be a shame if someone didn't properly clean up remnants
+  of a prior version of the document before publishing it
+hints:
+  - this is a real thing that happened that had real articles written about it
+files:
+  - src: ./23-719_19m2.pdf
+authors:
+  - Marvin
+visible: true

23-719/solve.txt

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+Refer to the following articles (as clued by the description/contents/hint):
+https://slate.com/news-and-politics/2024/03/supreme-court-metadata-sotomayor-trump-dissent.html
+https://abovethelaw.com/2024/03/supreme-court-accidentally-forgets-to-delete-basic-metadata-in-trump-ballot-ruling/
+
+The hidden text that, in the original PDF, said 
+  "SOTOMAYOR, J., concurring in part and dissenting in part",
+has been edited to read the flag,
+  "bcactf{rEAl_WOrLd_appLIc4t1ons_Of_cTf_ad04cc78601d5da8}".
+
+Several methods can be used to extract this text, such as:
+  1. simply copy/pasting, as in the above articles
+  2. directly using Ctrl+F in MacOS Preview
+  3. using Inspect Element in Firefox's PDF viewer
+  4. using a command-line utility like pdftotext.
+
+P.S. Creating this challenge was a bit harder than I expected.
+Many PDF editors could not edit (or sometimes even access) the text.