Trust in the Internet took a major blow on Tuesday as alarm spread that software commonly used to encrypt and secure online transactions could wind up giving away the store.
Computer security specialists, Web site masters and fans of online privacy were worriedly abuzz with word of a freshly discovered flaw in online data-scrambling software that hackers can turn to their advantage.
A bug dubbed “Heartbleed” in OpenSSL encryption software lets attackers illicitly retrieve passwords and other bits of information from working memory on computer servers, according to cyberdefense specialists at Fox-IT.
“Expect everybody who runs an https web server to be scrambling today,” the Tor Project said in a warning posted at its Web site.
“If you need strong anonymity or privacy on the Internet, you might want to stay away from the Internet entirely for the next few days while things settle,” it said.
OpenSSL is used to protect passwords, credit card numbers and other data coursing through the Internet.
Information considered at risk includes source codes, passwords and “keys” that could be used to impersonate Web sites or unlock encrypted data.
“These are the crown jewels, the encryption keys themselves,” said a heartbleed.com Web site devoted to details of the vulnerability.
“Leaked secret keys allows the attacker to decrypt any past and future traffic to the protected services and to impersonate the service at will,” it said.
The flaw in OpenSSL essentially allows a hacker to read the memory of a machine working the software, but no more than 64 kilobytes of data at a time, security specialists said.
Nor can hackers control which bits of memory are tapped, leaving to chance what they get their hands on.
However, hackers could repeatedly grab packets of memory to ramp up the odds of stealing valuable data.
“There is no limit on the number of attacks that can be performed,” Fox-IT said in a blog post that listed steps business information-technology handlers can take to thwart incursions.
Security researchers reported being able to dig out Yahoo password information by taking advantage of the bug. Yahoo released a statement on Tuesday saying it had fixed the problem at its main online properties.
Fox-IT estimated that the vulnerability has existed for about two years, since the version of OpenSSL at issue was released.
OpenSSL is used by more than half of Web sites, but not all versions have the vulnerability, according to heartbleed.com.
The group behind open-source OpenSSL put out a security alert urging users to upgrade to an improved version of the software and gave credit for finding the bug to Neel Mehta of Google Security.
Web sites will also need to change credentials used to verify authenticity to prevent hackers who may have looted the data from impersonating legitimate online venues and tricking visitors to enter valuable personal information.
As an added precaution, Internet users were advised to change passwords to online accounts or services they are intent on protecting.