Researcher finds way to send executable file on Facebook

Share this article:

Researchers have discovered a way to evade Facebook security controls to deliver a message on the social networking site that contains an executable file.

Facebook normally strips out messages that contain executables from its private messaging feature. But a yet-to-be-fixed vulnerability, discovered by penetration tester Nathan Power, could enable someone to undermine these security controls by altering the 'POST' request, which is used to send data to a server.

The researchers captured the POST query that is sent when attempting to upload an attachment, and altered the coding.

"It was discovered the variable 'filename' was being parsed to determine if the file type is allowed or not," according to the vulnerability disclosure. "To subvert the security mechanisms to allow an .exe file type, we modified the POST request by appending a space to our filename variable."

Doing this allowed the researchers to "trick the parser" and attach an executable to the message.

A bug like this is dangerous because it could allow criminals to send messages that contain malware. Power reported the vulnerability to Facebook on Sept. 30, and the company acknowledged its existence on Wednesday.

A Facebook spokesman, in an email to SCMagazineUS.com, said the exploit, as diagrammed by the researcher, would not impact a recipient.

"The attack...would only allow a user to send an obfuscated renamed file to another user, but this file would not execute on a recipients machine," the spokesman said, adding that Facebook also relies on anti-virus technology to weed out potentially malicious files.


Share this article:
You must be a registered member of SC Magazine to post a comment.

Sign up to our newsletters

TOP COMMENTS

More in News

ISSA tackles workforce gap with career lifecycle program

ISSA tackles workforce gap with career lifecycle program ...

On Thursday, the group launched its Cybersecurity Career Lifecycle (CSCL) program.

Amplification DDoS attacks most popular, according to Symantec

Amplification DDoS attacks most popular, according to Symantec

The company noted in a whitepaper released on Tuesday that Domain Name Server amplification attacks have increased 183 percent between January and August.

Court shutters NY co. selling security software with "no value"

A federal court shut down Pairsys at the request of the Federal Trade Commission.