Critical vulnerabilities remain in Apple's iCal calendar program, a security company said Wednesday in an advisory that showed months of back-and-forth between Apple and the researchers over whether bugs were serious enough to warrant patches, and if so, when Apple would patch them.
After several delays requested by Apple, the security vendor put its foot down and told the company's security team it would release information about the vulnerabilities May 21, whether Apple had issued patches or not.
In a bulletin posted to the Bugtraq and Full Disclosure mailing lists and on its own Web site, Core Security Technologies detailed three bugs in iCal that attackers could remotely exploit using compromised servers, malicious Web sites or e-mailed .ics file attachments.
"The vulnerabilities may allow un-authenticated attackers to execute arbitrary code on vulnerable systems with (and potentially without) the assistance from the end user of the application or to repeatedly execute a denial of service attack to crash the iCal application," said Core Security.
iCal is the scheduling and to-do application bundled with Mac OS X. It's used both as a standalone personal calendaring program and also as the client for connecting to Apple's calendar server.
Core Security first reported the iCal vulnerabilities and a fourth in iCal Server, a component of Mac OS X Server, on Jan. 30, 2008, but then spent nearly the next four months asking Apple when the company would patch the bugs, answering questions from Apple's security team and pushing back the deadline for publishing its findings.
In March, Apple said it considered only one of the three vulnerabilities a "security bug," according to Core Security, a stance that researchers there contested several times. "Vendor states that end of April is still the estimated date and provides more details that explain why the first two bugs are been considered null-pointer dereference bugs only," Core's timeline noted for April 17.
Later that day, Core said, it told Apple "the three bugs still have security-related consequences. Core considers bug[s] that allow unauthenticated third parties to be security vulnerabilities."
Apple patched the server-side vulnerability in March with Security Update 2008-002, a monster patch batch that included nearly 90 bug fixes; earlier, it had determined that the flaw was not in iCal Server, as Core Security had claimed, but in the Wiki Server instead.
But it was the patch planning for the iCal client that stretched on and on, said Core Security in the advisory. On four separate occasions, Apple requested that Core postpone the publishing of information about the vulnerabilities; each time Core agreed.
The problem: Apple kept shifting the deadline for delivering iCal patches.
According to Core, Apple first said it would fix iCal in time to make the 2008-002 update, which was released March 18, but when that proved impossible, changed the date to late April, then to early May, then finally to Monday, May 19.
After being asked May 10 to delay its disclosure a fifth time, Core Security said it would discuss rescheduling. Two days later, however, it told Apple it was setting Wednesday, May 21, as the drop-dead deadline. "Core communicates [to] the vendor that the publication of the advisory is re-scheduled to May 21, that date is final," Core Security noted in its bulletin.
The final advisory states that iCal 3.01 running in Mac OS X 10.5.1 is vulnerable, but it's unclear if that note was simply outpaced by events or is accurate; users running Mac OS X 10.5.2, the most current version of Leopard, are equipped with iCal 3.0.2. Core Security was not available for comment late Wednesday.
Apple has not patched the three iCal vulnerabilities spelled out by Core Security, and did not respond to queries Wednesday about when it would.