Facebook shrugs off alleged attachment vulnerability
- 29 October, 2011 00:24
- Comments
Facebook downplayed an alleged vulnerability in its social-networking site that could allow a hacker to send a potentially malicious file to anyone on Facebook.
The issue concerns a Facebook feature that allows a user to send another user who is not their friend a message as well as an attachment. Facebook prohibits sending executable files, but a security penetration tester found a way to circumvent the filter.
Nathan Power, who works for the technology consultancy CDW, wrote on his blog that Facebook parses part of a POST request to the server to see if the file being sent should be allowed.
If an executable is attached, Facebook warns that it can't be sent. But by modifying the POST request -- specifically with an extra space after the file name that is to be sent -- an executable could be attached. That poses a danger because it could allow a hacker to send, for instance, a keylogging program to another user in a kind of spear-phishing attach. The victim would then need to be convinced to open and run the file.
In a statement, Facebook's Security Manager Ryan McGeehan wrote that a successful attack would require "an additional layer of social engineering." It also only allows the attacker to send an obfuscated renamed file to another Facebook user one at a time.
Facebook doesn't rely solely on the identification of a file by what it purports to be in name to protect users but also does a security scan of files "so we have defense in depth for this sort of vector," McGeehan wrote. He also said that webmail providers face the same problem with malicious attachments and that "this finding is a very small part of how we protect against this threat overall."
"At the end of the day, it is more practical for a bad guy to hide an .exe on a convincing landing page behind a URL shortener, which is something we've been dealing with for a while," McGeehan wrote.
Power wrote Facebook was notified of the issue on Sept. 30 and the company acknowledged the issue on Wednesday.
Send news tips and comments to jeremy_kirk@idg.com
Join the CIO Australia group on LinkedIn. The group is open to CIOs, IT Directors, COOs, CTOs and senior IT managers.
- Bookmark this page
- Share this article
- Got more on this story? Email CIO
- Follow CIO on twitter
-
Australia Post’s mail business to lose $200 million this year
-
Australia Post’s mail business to lose $200 million this year
-
Microsoft's ambivalence about Office on the Web gives Apple shot with iWork on iCloud
-
3 Lessons Learned From a Failed Customer Feedback Test
-
Online shopping reaches mainstream status
-
Maximising productivity without sacrificing security
Advances in mobility and client computing technology combined with the ubiquity of the Internet and social media are creating a culture and desire for constant connectivity and anywhere access to information. As these trends extend from the home into the work place, IT managers should consider seriously the opportunities for increased productivity and communication with customers and constituents, as well as understand the increased security risks posed by online, anytime access to private networks and data. Read more. -
The Foundation for Cloud Management
For businesses looking to provide real-time business solutions to employees and customers alike, you need to have a comprehensive network management strategy. The network is the foundation of all successful cloud services; it must be robust to meet traffic, efficiency, and performance demands. Download today the four steps to get your network operations cloud-ready. -
Top 10 Mistakes in Data Centre Operations: Operating Efficient and Effective Data Centres
How can you avoid making major mistakes when operating and maintaining your data centre(s)? The key lies in the methodology behind your operations and maintenance program. This whitepaper explores the top ten mistakes in data centre operations. Read now.

















