[BZ#2434] Problem decoding some FAX4 images
Submitted by Jason Summers (jason1 at pobox dot com) on 2013-04-19 09:09
Description
Created an attachment (id=503)
Sample TIFF file
The attached file can be decoded by libtiff 3.9.4, but not by libtiff 3.9.5 and newer. The difference is caused by the fix for CVE-2011-0192.
Test case: Using libtiff 4.0.3,
$ tiffcp -c none testfax4.tif tmp.tif
Actual result: Many warnings, starting with
Fax4Decode: Bad code word at line 462 of strip 0 (x 2452).
Fax4Decode: Warning, Premature EOL at line 462 of strip 0 (got 2452, expected 2453).
Fax4Decode: Warning, Line length mismatch at line 463 of strip 0 (got 2460, expected 2453).
Fax4Decode: Warning, Line length mismatch at line 465 of strip 0 (got 2454, expected 2453).
...
The image is garbled starting at the first line reported in the warnings.
Expected result: Maybe a warning message, but I would hope that the image could still be decoded as it is by v3.9.4. Most TIFF viewers successfully decode it.
Attachment 503, "Sample TIFF file":
testfax4.tif
Attachment 528, "Error pattern analysis on previously submitted image":
libtiff-bug-2434-analysis.ods