Feeds

Filthy! old! blog! bug! blamed! for! Yahoo! webmail! hijacks!

Unpatched WordPress flaw clears way for inbox takeovers

Internet Security Threat Report 2014

Yahoo! webmail accounts are being hijacked by hackers exploiting an eight-month-old bug in the web giant's blog, security biz Bitdefender warns.

Messages with a short link to an apparently harmless MSNBC web-page are being spread to compromise mailboxes: the link actually points to a completely different website hosting malicious JavaScript code that swipes the victim's browser cookie used to log into Yahoo! mail.

Once this cookie is in the hands of miscreants, they can use it to access the vicim's mail account. The domain serving up this cross-site scripting attack code was registered in Ukraine on 27 January and the web server is hosted in Cyprus.

The JavaScript exploits an old WordPress blog security hole in developer.yahoo.com to lift the user's mail.yahoo.com cookie. Using this harvested information, crooks can masquerade as the victim to send spam or pinch contacts’ e-mail addresses.

“The attack focuses on the Yahoo Developers Blog, which uses a buggy version of WordPress that has a security flaw known as CVE-2012-3414," said Catalin Cosoi, chief security strategist at Bitdefender, referring to this Flash applet bug.

"This flaw has been patched since WordPress version 3.3.2. Since it is located on a sub-domain of the yahoo.com website, the attackers trigger the bug and pass a command that steals the cookie and sends it 'home'. At this point, they have full access to the victim’s contact list until the current session expires or the user logs out.”

Bitdefender said the ongoing campaign highlights two risks: the dangers of clicking on links in emails and problems that can arise when a website is vulnerable to cross-site scripting attacks, a common class of security vulnerability. The Yahoo! hijack also illustrates the important role played by cookies in applications such as webmail.

“Security on the web is based on the same-origin policy, a complex mechanism that won’t allow Site A to access resources of Site B, such as cookies," Cosoi said.

"Cookies are small snippets of text created when the user logs into a system, and they are used to (among other things) remember that the account holder has already passed the authentication once. Otherwise, the user will have to log in whenever they read another e-mail or when they navigate from one page to another.

“So, in this context, it is obvious that a piece of code running on Site A can’t steal a cookie set by Site B. However, a subdomain of Site B can access the resources of Site B, and this is what the attackers did."

Bitdefender has a write-up of the attack on its antivirus labs blog here. ®

Internet Security Threat Report 2014

More from The Register

next story
George Clooney, WikiLeaks' lawyer wife hand out burner phones to wedding guests
Day 4: 'News'-papers STILL rammed with Clooney nuptials
Shellshock: 'Larger scale attack' on its way, warn securo-bods
Not just web servers under threat - though TENS of THOUSANDS have been hit
Apple's new iPhone 6 vulnerable to last year's TouchID fingerprint hack
But unsophisticated thieves need not attempt this trick
PEAK IPV4? Global IPv6 traffic is growing, DDoS dying, says Akamai
First time the cache network has seen drop in use of 32-bit-wide IP addresses
Oracle SHELLSHOCKER - data titan lists unpatchables
Database kingpin lists 32 products that can't be patched (yet) as GNU fixes second vuln
Who.is does the Harlem Shake
Blame it on LOLing XSS terroristas
Researchers tell black hats: 'YOU'RE SOOO PREDICTABLE'
Want to register that domain? We're way ahead of you.
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
The next step in data security
With recent increased privacy concerns and computers becoming more powerful, the chance of hackers being able to crack smaller-sized RSA keys increases.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.