In an interview with Computerworld earlier this week, Appelbaum argued that the delay in disclosing information put Iranian anti-government activists' lives at risk.
"By keeping this quiet for eight days, Comodo and others put lives at risk," charged Appelbaum. "[Iranian activists] were completely unable to protect themselves during that time. Users should have had this information sooner."
And he dismissed the idea that Comodo and the browser makers, particularly Mozilla, should worry about "responsible disclosure" -- the practice of withholding information about a security bug until a fix is ready -- because the underlying problem was not a vulnerability that others could exploit.
"This is not a normal attack. Disclosure does not allow anyone else to perform this attack -- only the attacker with the certificate is able to take advantage of this situation," Appelbaum told Mozilla. "Only the attacker will benefit from a delay."
In a back-and-forth on Bugzilla, the Firefox bug- and change-tracking database, Appelbaum also pushed Mozilla to change the way that Firefox handles OCSP (online certificate status protocol), which is used to determine if a certificate has been revoked by an issuing authority, such as Comodo.
"I really think enabling OCSP to 'required' is the minimum safe thing to do," Appelbaum wrote on Bugzilla March 18, "It's a work around that will fail closed and while it's a bad thing, it seems like the best out of all of a bunch of bad choices."
At times, Appelbaum was scathing in his criticism of Mozilla's refusal to publicly disclose the theft and warn Firefox users.
"Firefox has majorly dropped the ball here," he said Tuesday on Bugzilla. "After the entire CA [certificate authority] model has shown time and time again to be security nightmare, Firefox should have led the way. That's what the Internet expects from Mozilla and it's what I expect from Mozilla."
Appelbaum said some of the same in his interview with Computerworld on Wednesday.
"This was a gigantic failure on Mozilla's part," Appelbaum said then. "They believe disclosure will harm users. That's bogus."
Appelbaum did not reply to an e-mail today requesting comment on Mozilla's mea culpa.
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