Adobe plans to update its Lightroom software and Camera Raw plug-in for Photoshop next week to address a "potentially severe bug" involving JPEG files.
The problem could affect people saving JPEG images taken with cameras that store large amounts of private camera information in the file's metadata--textual information such as captions, keywords, and titles that can accompany the actual photo.
This bug only impacts customers who are saving metadata to JPEG files with a rare characteristic. (JPEG files must have an unusually large block of private camera data included in the file to be susceptible to the bug.) This scenario is so rare that we do not believe that it is necessary for customers who have already upgraded to revert to the previous version of Lightroom or Camera Raw. However, the bug could cause image corruption which falls within our highest severity category of bugs...
If you do work with a significant number of JPEG files in Lightroom or Camera Raw and routinely update metadata (keywords, captions, etc) it would be prudent to wait for the updated release of Lightroom and Camera Raw.
Lightroom 3.4.1 and Camera Raw 6.4.1 are scheduled for release by May 27, he said.