ITWire

"As the name suggests, the Public shares are available to anyone without authentication. Given the default permissions on home directories (world read+execute) and the default umask (world read), this has a serious impact - as unauthenticated users can read all files in a user's home directory. The attack also works for authenticated users against shares requiring authentication.

"Technically the attack is not very challenging and relies on a classic directory traversal attack. It is strikingly similar to the famous Windows SMB filesharing vulnerability from 1995."

The vulnerability was first disclosed to Apple on February 10th and after numerous delays, Apple finally agreed to full disclosure occurring overnight (March 29th US time).

In addition to outlining the vulnerability, the author also provides a simple test to detect whether a target system is vulnerable.

Quoting the discoverer:

Here is the syntax for running the scripts against a system or network to detect vulnerable hosts [using a script available from the NMAP website]:

nmap -p 548 --script afp-path-vuln
If the server is vulnerable it will show the following output:

PORT    STATE SERVICE
548/tcp open  afp
| afp-path-vuln:
|   Patrik's Public Folder/../ (5 first items)
|     .bash_history
|     .bash_profile
|     .CFUserTextEncoding
|     .config/
|     .crash_report_checksum
|
|_AFP path traversal (CVE-2010-0533): VULNERABLE

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