Cloudflare parser bug discovered to have been leaking sensitive data, Hovatek was not affected.

The internet has been set agog by news of the Cloudflare bug which might have been leaking sensitive user data from websites using Cloudflare. You can see the full blog post for details on the bug. This bug causes random chunks of personal information from Cloudflare protected websites to be saved to stranger’s browser.

The source of the vulnerability was a piece of code which was supposed to check the buffer size
/* generated code. p = pointer, pe = end of buffer */
if ( ++p == pe )
goto _test_eof;

What happens is that elsewhere p becomes greater than pe, thus it avoids the length check, allowing the buffer to overflow with extra information. This eventually leads to web session leaks .

Hovatek got an email from Cloudflare stating that we had not been affected but we still think you should take certain precautions. Here’s the email:

Dear Cloudflare Customer:

Thursday afternoon, we published a blog post describing a memory leak caused by a serious bug that impacted Cloudflare’s systems. If you haven’t yet, I encourage you to read that post on the bug:

While we resolved the bug within hours of it being reported to us, there was an ongoing risk that some of our customers’ sensitive information could still be available through third party caches, such as the Google search cache.

Over the last week, we’ve worked with these caches to discover what customers may have had sensitive information exposed and ensure that the caches are purged. We waited to disclose the bug publicly until after these caches could be cleared in order to mitigate the ability of malicious individuals to exploit any exposed data.

In our review of these third party caches, we discovered data that had been exposed from approximately 150 of Cloudflare’s customers across our Free, Pro, Business, and Enterprise plans. We have reached out to these customers directly to provide them with a copy of the data that was exposed, help them understand its impact, and help them mitigate that impact.

Fortunately, your domain is not one of the domains where we have discovered exposed data in any third party caches. The bug has been patched so it is no longer leaking data. However, we continue to work with these caches to review their records and help them purge any exposed data we find. If we discover any data leaked about your domains during this search, we will reach out to you directly and provide you full details of what we have found.

To date, we have yet to find any instance of the bug being exploited, but we recommend if you are concerned that you invalidate and reissue any persistent secrets, such as long lived session identifiers, tokens or keys. Due to the nature of the bug, customer SSL keys were not exposed and do not need to be rotated.

Again, if we discover new information that impacts you, we will reach out to you directly. In the meantime, if you have any questions or concerns, please don’t hesitate to reach out.

Matthew Prince
Cloudflare, Inc.
Co-founder and CEO

As a safety precaution, we advise that you change your Hovatek Forum password! If you use any Cloudflare protected website or use the same password on multiple websites then its advisable to change your password(s) immediately.
Team Hovatek remains committed to protecting your sensitive data and will promptly inform you if there’s a breach.