Slow scanning on computers with many image files

  • Article ID: 12953
  • Rating:
  • 2 customers rated this article 4.5 out of 6
  • Updated: 09 Jan 2014

On-demand scans with Sophos Anti-Virus could run slowly on computers with very large numbers of JPG or JPEG files.

JPG, JPEG and WMF extensions were added to the default list of executables scanned, as a result of the discovery of the Windows Metafile (WMF) vulnerability (see Microsoft Security Advisory 912840). This could affect scanning speed on computers with large collections of images.

You can exclude files with JPG and JPEG extensions from scanning, or scan collections of such files separately. If you do either, you must ensure that you have installed the patch referred to in Microsoft Security Advisory 912840.

Applies to the following Sophos product(s) and version(s)

Sophos Endpoint Security and Control
Sophos Anti-Virus for Windows 2000+

What To Do

Scanning picture collections with a separate scheduled scan

  1. Install the patch linked to from Microsoft Security Advisory 912840, and check that it is in the list of installed patches.
  2. Set up a scheduled scan of your picture collection folders for a quiet time (e.g. Sunday afternoon).
  3. Exclude your picture collection folders from your usual scheduled scan.

This will ensure that the scan takes place at the most convenient time, but it will slow the system at that time.

Exclude JPG and JPEG files from scanning

  1. Install the patch linked to from Microsoft Security Advisory 912840, and check that it is in the list of installed patches.
  2. Exclude JPG and JPEG file extensions from scanning (you are unlikely to have large numbers of WMF files, so there should be no need to exclude these).

Note: The Microsoft patch will protect you against the Windows Metafile (WMF) vulnerability, but excluding JPG and JPEG file extensions from scanning could leave your computer open to any new exploit involving JPG and JPEG files.

 
If you need more information or guidance, then please contact technical support.

Rate this article

Very poor Excellent

Comments