mailscanner 4.68.8 and other versions before 4.74.16-1 might allow local users to overwrite arbitrary files via a symlink attack on certain temporary files used by the (1) f-prot-autoupdate, (2) clamav-autoupdate, (3) avast-autoupdate, and (4) f-prot-6-autoupdate scripts in /etc/MailScanner/autoupdate/; the (5) bitdefender-wrapper, (6) kaspersky-wrapper, (7) clamav-wrapper, and (8) rav-wrapper scripts in /etc/MailScanner/wrapper/; the (9) Quarantine.pm, (10) TNEF.pm, (11) MessageBatch.pm, (12) WorkArea.pm, and (13) SA.pm scripts in /usr/share/MailScanner/MailScanner/; (14) /usr/sbin/MailScanner; and (15) scripts that load the /etc/MailScanner/mailscanner.conf.with.mcp configuration file.
Weakness
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Mailscanner | Mailscanner | 4.68.8 (including) | 4.68.8 (including) |
| Mailscanner | Mailscanner | 4.68.8-1 (including) | 4.68.8-1 (including) |
| Mailscanner | Mailscanner | 4.69.9-3 (including) | 4.69.9-3 (including) |
| Mailscanner | Mailscanner | 4.70.7-1 (including) | 4.70.7-1 (including) |
| Mailscanner | Mailscanner | 4.71.10-1 (including) | 4.71.10-1 (including) |
| Mailscanner | Mailscanner | 4.72.5-1 (including) | 4.72.5-1 (including) |
| Mailscanner | Mailscanner | 4.73.4-2 (including) | 4.73.4-2 (including) |
| Mailscanner | Ubuntu | dapper | * |
| Mailscanner | Ubuntu | gutsy | * |
| Mailscanner | Ubuntu | hardy | * |
| Mailscanner | Ubuntu | intrepid | * |
| Mailscanner | Ubuntu | upstream | * |
Potential Mitigations
- Follow the principle of least privilege when assigning access rights to entities in a software system.
- Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/132.html
- https://cwe.mitre.org/data/definitions/17.html
- https://cwe.mitre.org/data/definitions/35.html
- https://cwe.mitre.org/data/definitions/76.html
References
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=506353#44
- http://secunia.com/advisories/33117
- http://www.mailscanner.info/ChangeLog
- http://www.openwall.com/lists/oss-security/2008/11/29/1
- http://www.securityfocus.com/bid/32557
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=506353#44
- http://secunia.com/advisories/33117
- http://www.mailscanner.info/ChangeLog
- http://www.openwall.com/lists/oss-security/2008/11/29/1
- http://www.securityfocus.com/bid/32557