======= Summary ======= Name: Heap overflow in RealPlayer ID3 tag parsing code Release Date: 29 October 2007 Reference: NGS00432 Discover: John Heasman Vendor: RealNetworks Systems Affected: Several builds of RealPlayer 10.5, All builds of RealPlayer 10. For additional affected versions, see the URL below. Risk: High Status: Published ======== TimeLine ======== Discovered: 1 August 2006 Released: 1 August 2006 Approved: 1 August 2006 Reported: 1 August 2006 Fixed: 25 October 2007 Published: 29 October 2007 =========== Description =========== There is a heap overflow in the Realplayer code that parses ID3 tags in MP3 files. Impact: attackers could execute code of their choice on susceptible systems if a user were induced to open a malicious MP3 file. ================= Technical Details ================= The problem stems from the parsing of a Lyrics3 v2.00 tag. The size of the tag is calculated by reading 5 ASCII characters and calling pncrt.atoi. A buffer is then allocated on the heap of size tag length + 1. Since atoi parses a signed integer, supplying -1, results in a zero length allocation into which data is copied. This can be exploited to overwrite a function pointer leading to the execution of arbitrary attacker-supplied code in the context of the user under which RealPlayer is running. =============== Fix Information =============== This issue has now been resolved. Steps detailing how to update RealPlayer may be obtained from: http://service.real.com/realplayer/security/10252007_player/en/ NGSSoftware Insight Security Research http://www.ngssoftware.com/ http://www.databasesecurity.com/ http://www.nextgenss.com/ +44(0)208 401 0070 -- E-MAIL DISCLAIMER The information contained in this email and any subsequent correspondence is private, is solely for the intended recipient(s) and may contain confidential or privileged information. For those other than the intended recipient(s), any disclosure, copying, distribution, or any other action taken, or omitted to be taken, in reliance on such information is prohibited and may be unlawful. If you are not the intended recipient and have received this message in error, please inform the sender and delete this mail and any attachments. The views expressed in this email do not necessarily reflect NGS policy. NGS accepts no liability or responsibility for any onward transmission or use of emails and attachments having left the NGS domain. NGS and NGSSoftware are trading names of Next Generation Security Software Ltd. Registered office address: 52 Throwley Way, Sutton, SM1 4BF with Company Number 04225835 and VAT Number 783096402