Mono: Insecure temporary file creation

1.  Gentoo Linux Security Advisory

Version Information

Related bugreports: #150264

Synopsis

Mono is vulnerable to linking attacks, potentially allowing a local user to overwrite arbitrary files.

2.  Impact Information

Background

Mono provides the necessary software to develop and run .NET client and server applications.

Description

Sebastian Krahmer of the SuSE Security Team discovered that the System.CodeDom.Compiler classes of Mono create temporary files with insecure permissions.

Impact

A local attacker could create links in the temporary file directory, pointing to a valid file somewhere on the filesystem. When an affected class is called, this could result in the file being overwritten with the rights of the user running the script.

3.  Resolution Information

Workaround

There is no known workaround at this time.

Resolution

All Mono users should upgrade to the latest version:

# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-lang/mono-1.1.13.8.1"

4.  References

• CVE-2006-5072