Vulnerability Note VU#596848

gzip contains an infinite loop vulnerability in its LZH handling

A infinite loop vulnerability exists in the way gzip handles certain files. An attacker may be able to exploit this vulnerability by convincing a user to open a specially crafted gzip file.

Note that the attacker could either convince a user to open a malicious gzip file, or save the file in a place where another program would call gzip to decompress the archive.

II. Impact

This issue has been addressed in gzip 1.3.6. See the systems affected section of this document for information about specific vendors.

Workarounds
Until updates can be applied, the following workarounds may mitigate the impact of this vulnerability:

• Do not decompress gzip files that are received from unknown sources.
• Do not execute gzip with system-level privileges.
• Some automated processes may rely on gzip to complete their tasks. When possible, disable such programs or do not allow them to execute gzip with root privileges.

http://www.gzip.org/
http://www.auscert.org.au/7179

Credit

Thanks to Tavis Ormandy, Google Security Team for reporting this issue.

This document was written by Ryan Giobbi.

Other Information

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