Serious Exploit in Windows Media Player (WMP)

The New Acunetix V12 Engine


Oh look! Another 0-day in Windows…this time in Media Player, there was a few in Word lately and the latest thing that just hit is an XSS flaw in PDF files online.

I’ll report more on those later.

The Windows Media Player library WMVCORE.DLL contains a potentially exploitable heap buffer overflow in its handling of “REF HREF” URLs within ASX files. If the URL contains an unrecognized protocol (only “file”, “ftp”, “http”, “https”, “mms”, “mmst”, “mmsu”, “rtsp”, “rtspt”, and “rtspu” appear to be recognized), the function at 7D7A8F27 in WMVCORE.DLL version 9.0.0.3250, and at 086E586E in WMVCORE.DLL version 10.0.0.3802, will create a copy of the string in which the protocol is replaced with “mms”. A heap buffer is allocated, the string “mms” is copied into it, and then everything after and including “://” in the “REF HREF” URL is concatenated using wcsncat.

So what out what you are streaming..please! Or alternatively use something decent like Winamp.

Unfortunately, the heap buffer for the new “mms” URL is allocated to the size of the “REF HREF” URL, and even more unfortunately, the length of the input string being passed to wcsncat is supplied as the character count, effectively causing wcsncat to behave identically to wcscat. As a result, a two- or four-byte heap overflow is possible if the “REF HREF” URL features a protocol shorter than three characters (the length of “mms”).

Single-letter protocols (such as “a://”) are rejected, but this restriction can be circumvented by encoding the protocol (“%61://”), thereby making a four-byte overflow possible.

Exploitability due to the corruption of the adjacent heap block’s header is assumed likely but research is ongoing.

As far as I know there’s no current exploit for this, but it is a possibility.

Source: eEye

Posted in: Exploits/Vulnerabilities, Windows Hacking

, , ,


Latest Posts:


Insecure software versions are a problem Web Security Stats Show XSS & Outdated Software Are Major Problems
Netsparker just published some anonymized Web Security Stats about the security vulnerabilities their online solution identified on their users’ web applications and web services during the last 3 years.
CTFR - Abuse Certificate Transparency Logs For HTTPS Subdomains CTFR – Abuse Certificate Transparency Logs For HTTPS Subdomains
CTFR is a Python-based tool to Abuse Certificate Transparency Logs to get subdomains from a HTTPS website in a few seconds.
testssl.sh - Test SSL Security Including Ciphers, Protocols & Detect Flaws testssl.sh – Test SSL Security Including Ciphers, Protocols & Detect Flaws
testssl.sh is a free command line tool to test SSL security, it checks a server's service on any port for the support of TLS/SSL ciphers, protocols as well as recent cryptographic flaws and more.
Four Year Old libSSH Bug Leaves Servers Wide Open Four Year Old libssh Bug Leaves Servers Wide Open
A fairly serious 4-year old libssh bug has left servers vulnerable to remote compromise, fortunately, the attack surface isn't that big as neither OpenSSH or the GitHub implementation are affected.
CHIPSEC - Platform Security Assessment Framework CHIPSEC – Platform Security Assessment Framework For Firmware Hacking
CHIPSEC is a platform security assessment framework for PCs including hardware, system firmware (BIOS/UEFI), and platform components for firmware hacking.
How To Recover When Your Website Got Hacked How To Recover When Your Website Got Hacked
The array of easily available Hacking Tools out there now is astounding, combined with self-propagating malware, people often come to me when their website got hacked and they don't know what to do, or even where to start.


One Response to Serious Exploit in Windows Media Player (WMP)

  1. Sypherknife June 5, 2007 at 12:41 pm #

    …”Or alternatively use something decent like Winamp.”

    If only people realised that there are alternatives to shit programs