ClamAV: Multiple Denials of Service

Security Team Contact Address

Updated June 15, 2007

1. Gentoo Linux Security Advisory

Advisory Reference	GLSA 200706-05 / clamav
Release Date	June 15, 2007
Latest Revision	June 15, 2007: 01
Impact	normal
Exploitable	remote, local

Package	Vulnerable versions	Unaffected versions	Architecture(s)
app-antivirus/clamav	< 0.90.3	>= 0.90.3	All supported architectures

Related bugreports: #178082

Synopsis

ClamAV contains several vulnerabilities leading to a Denial of Service.

2. Impact Information

Background

ClamAV is a GPL virus scanner.

Description

Several vulnerabilities were discovered in ClamAV by various researchers:

Victor Stinner (INL) discovered that the OLE2 parser may enter in an infinite loop (CVE-2007-2650).
A boundary error was also reported by an anonymous researcher in the file unsp.c, which might lead to a buffer overflow (CVE-2007-3023).
The file unrar.c contains a heap-based buffer overflow via a modified vm_codesize value from a RAR file (CVE-2007-3123).
The RAR parsing engine can be bypassed via a RAR file with a header flag value of 10 (CVE-2007-3122).
The cli_gentempstream() function from clamdscan creates temporary files with insecure permissions (CVE-2007-3024).

Impact

A remote attacker could send a specially crafted file to the scanner, possibly triggering one of the vulnerabilities. The two buffer overflows are reported to only cause Denial of Service. This would lead to a Denial of Service by CPU consumption or a crash of the scanner. The insecure temporary file creation vulnerability could be used by a local user to access sensitive data.

3. Resolution Information

Workaround

There is no known workaround at this time.

Resolution

All ClamAV users should upgrade to the latest version:

Code Listing 3.1: Resolution

# emerge --sync
# emerge --ask --oneshot --verbose ">=app-antivirus/clamav-0.90.3"

4. References