"As a pentester who does attacks similar to what the ComodoHacker did, I find it credible," Graham said Sunday on the Errata blog. "I find it probable that (1) this is the guy, (2) he acted alone, (3) he is Iranian, (4) he's patriotic but not political."
But Mikko Hypponen, the chief research officer of Helsinki-based F-Secure, sounded skeptical.
"Do we really believe that a lone hacker gets into a [certificate authority], can generate any cert he wants...and goes after login.live.com instead of paypal.com?" asked Hypponen on Twitter.
Graham had an answer for Hypponen's question.
"[Comodo Hacker] started with one goal, that of factoring RSA keys, and ended up reaching a related goal, forging certificates," said Graham. "He didn't think of PayPal because he wasn't trying to do anything at all with the forged certificates."
ComodoHacker also lit into the West -- Western media in particular -- for quickly concluding that the Iranian government was involved when it had downplayed possible U.S. and Israeli connections to Stuxnet, the worm that most experts believe was aimed at Iran's nuclear program.
He also threatened to unleash his skills against those he said were enemies of Iran.
"Anyone inside Iran with problems, from fake Green Movement to all MKO members and two-faced terrorists, should [be] afraid of me personally," said ComodoHacker. "I won't let anyone inside Iran, harm people of Iran, harm my country's Nuclear Scientists, harm my Leader (which nobody can), harm my President."
MKO, or the "People's Mujahedin of Iran," is an Islamic group that advocates the overthrow of the current government of Iran.
"As I live, you don't have privacy in Internet, you don't have security in digital world, just wait and see," ComodoHacker said.
Comodo was not available Sunday for comment on ComodoHacker's claims.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed. His email address is email@example.com.
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