The Lotus Domino Web Server contains a flaw that could be exploited to cause a denial of service.
HTTP requests with uniquely crafted headers using "Accept", "Accept-Charset", "Accept-Encoding", "Accept-Language" or "Content-Type" are not freed properly. This means that submitting numerous requests for a document, such as root (/), with various accept fields (accept: a, accept: aa, accept: aaa, ...) will cause the server to run out of physical memory. The server will then display an error message similar to this one:
"HTTP Server: Could allocate 8036 bytes of memoryOut of memory in HTMemPoolAlloc (file htmpool.c, line 506).Program aborted."
The server will eventually run out of physical memory and a denial of service will result.
An application layer filter may be able to detect and block unapproved requests.
Our thanks to Defcom Labs, which published an advisory on this and other problems, available at http://www.securityfocus.com/frames/?content=/templates/advisory.html?id=3208.
This document was written by Jason Rafail and is based on information obtained from a Defcom Labs Advisory.
|Date First Published:||2001-07-12|
|Date Last Updated:||2001-07-17 19:15 UTC|