A security vulnerability identified in Opera can be exploited to crash users' browsers, but probably can't lead to the remote execution of malware, a company spokesman said.
The buffer overflow bug was disclosed by Vupen Security on Thursday, and the report has since been picked up by others, including Secunia and Sans. The advisories have said the vulnerability is critical because it can be exploited to remotely execute malicious code on end user machines.
Vupen officials didn't respond to emails seeking details. But Opera isn't so sure.
"We believe that the bug primarily causes a crash, and that exploiting the vulnerability to execute code is extremely difficult, if not impossible," spokesman Thomas Ford told The Register. He went on to say that users should be sure to enable a security feature known as DEP, or data execution prevention.
"In our testing, DEP mitigates the problem and should protect the system," he said.
Thing is, DEP isn't always turned on by default. If you use Windows XP, follow the instructions here to make sure you're protected. Users of Vista and Windows 7 can find details here and here. The changes will prevent Windows from executing code when loaded into memory by a variety of third-party applications.
Apple provides similar protections. Readers who know whether Opera is automatically protected on Macs are encouraged to leave a comment.
Researchers have figured out ways to bypass DEP and a similar protection known as ASLR, or address space layout randomization, but at the moment those techniques are extremely difficult for the average exploit writer to pull off.
Ford said Opera is in the process of pushing out an update that patches the bug. ®