Email virus scanning software relying on Archive::Zip can be fooled into thinking a ZIP attachment is empty while it contains a virus, allowing detection evasion.
| Package | Arch | Vulnerable | Unaffected |
|---|---|---|---|
| dev-perl/Archive-Zip | * | < 1.14 | >= 1.14 |
Archive::Zip is a Perl module containing functions to handle ZIP archives.
Archive::Zip can be used by email scanning software (like amavisd-new) to uncompress attachments before virus scanning. By modifying the uncompressed size of archived files in the global header of the ZIP file, it is possible to fool Archive::Zip into thinking some files inside the archive have zero length.
An attacker could send a carefully crafted ZIP archive containing a virus file and evade detection on some email virus-scanning software relying on Archive::Zip for decompression.
There is no known workaround at this time.
All Archive::Zip users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=dev-perl/Archive-Zip-1.14"