[SingCERT] IBM Lotus Notes Multiple Heap Based Buffer Overflow Vulnerabilities

Last Updated on Thursday, 26 May 2011 17:05

[Summary]

IBM Lotus Notes is prone to multiple heap-based buffer-overflow vulnerabilities

 [Affected Systems]
IBM Lotus Notes is prone to the following heap-based buffer-overflow vulnerabilities:

1.     A heap-based buffer-overflow vulnerability affects the XLS viewer when handling '.xls' files containing a malformed BIFF record.

2.     Multiple heap-based buffer-overflow vulnerabilities when handling the following file formats:

• Microsoft Office document
• Lotus Notes '.prz' file
• Lotus Notes '.zip' file
• LZH archive
• RTF document
• Applix Spreadsheets

An attacker can exploit these issues by enticing an unsuspecting victim to open a malicious file. Successful exploits can allow attackers to execute arbitrary code with the privileges of the user running the application.

[Impact Analysis]
An attacker can exploit these issues to execute arbitrary code with the privileges of the user running the application. Failed exploit attempts will result in a denial-of-service condition.

[Solution/Workaround]
Run all software as a nonprivileged user with minimal access rights. To reduce the impact of latent vulnerabilities, always run nonadministrative software as an unprivileged user with minimal access rights.

Deploy network intrusion detection systems to monitor network traffic for malicious activity. Deploy NIDS to monitor network traffic for signs of suspicious or anomalous activity. This may help detect malicious actions that an attacker may take after successfully exploiting vulnerabilities in applications. Review all applicable logs regularly.

 Do not accept or execute files from untrusted or unknown sources. To reduce the likelihood of successful exploits, never handle files that originate from unfamiliar or untrusted sources.

 Do not follow links provided by unknown or untrusted sources. Web users should be cautious about following links to sites that are provided by unfamiliar or suspicious sources. Filtering HTML from emails may help remove a possible vector for transmitting malicious links to users. 

Implement multiple redundant layers of security. Since this issue may be leveraged to execute code, we recommendmemory-protection schemes, such as nonexecutable stack/heap configurations and randomly mapped memory segments. This tactic may complicate exploits of memory-corruption vulnerabilities.

The vendor has released  an advisory and updates. Please see the references for details.

[Reference]
        ·         https://www-304.ibm.com/support/docview.wss?uid=swg21500034

·         http://www-01.ibm.com/software/lotus/products/notes/

·         http://www.coresecurity.com/content/LotusNotes-XLS-viewer-heap-overflow