Security experts have expressed doubts about a hacker claim that there's a new vulnerability in the patched version of OpenSSL, the widely used cryptographic library repaired in early April.
A group of five hackers writes in a posting on Pastebin that they worked for two weeks to find the bug and developed code to exploit it. They've offered the code for the price of 2.5 bitcoins, around US$870.
A new flaw in OpenSSL could pose just as much of a threat as Heartbleed did. But the hackers' claim was met with immediate suspicion on Full Disclosure, a forum for discussing vulnerability reports.
One commentator, Todd Bennett, wrote the technical description of their claim is "rather extraordinary."
The open-source OpenSSL code is used by millions of web sites to create encrypted communications between client computers and servers. The flaw disclosed in early April, nicknamed "Heartbleed," can be abused to reveal login credentials or a server's private SSL key.
More than two-thirds of the websites affected by the flaw have patched OpenSSL, according to McAfee.
The hackers said they've found a buffer overflow vulnerability that is similar to Heartbleed. They claim they've spotted a missing bounds check in the handling of the variable "DOPENSSL_NO_HEARTBEATS."
"We could successfully overflow the 'DOPENSSL_NO_HEARTBEATS' and retrieve 64kb chunks of data again on the updated version," they wrote.
They have not published their exploit code, so there is no way to verify their claim. The group provided an email address for questions, but did not immediately respond to a query.
A Google search showed the same email address has been used in other offers for data on Pastebin. In March, it was used in a Pastebin posting advertising a trove of data from Mt. Gox, the defunct Tokyo-based bitcoin exchange that was hacked.
The same advertisement also offered database dumps from "carding" websites, or those selling stolen credit card data, and data from CryptoAve, another virtual currency exchange that's been attacked by hackers. Scammers often try to make money by falsely claiming they have data of interest to the hacking community.
The Heartbleed flaw has since touched off an effort to strengthen the security of widely used open-source products. The OpenSSL Project, for example, had just one full-time employee and only received about $2,000 in donations annual despite its critical role in protecting communications.
On Thursday, a group of technology companies and organizations launched the Core Infrastructure Initiative, a project intended to generate funds for full-time developers on important open-source products.
The group's participants include Amazon Web Services, Cisco, Dell, Facebook, Fujitsu, Google, IBM, Intel, Microsoft, NetApp, Rackspace, VMware and The Linux Foundation.
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