CVE-2018-6335: Input Validation

Published Dec 31, 2018
·
Updated

A Malformed h2 frame can cause 'std::outofrange' exception when parsing priority meta data. This behavior can lead to denial-of-service. This affects all supported versions of HHVM (3.25.2, 3.24.6, and 3.21.10 and below) when using the proxygen server to handle HTTP2 requests.

Affected Software

3 affected components
Facebook HHVM<=3.21.10
Facebook HHVM=3.24.6
Facebook HHVM=3.25.2

Event History

Dec 31, 2018
CVE Published
07:29 PM
CVE Published
via MITRE·08:00 PM
Data Sourced
via MITRE·08:00 PM
DescriptionWeakness
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Frequently Asked Questions

1

What is CVE-2018-6335?

CVE-2018-6335 is a vulnerability in Facebook HHVM where a malformed h2 frame can cause a 'std::out_of_range' exception when parsing priority metadata, leading to a denial-of-service.

2

How does CVE-2018-6335 affect HHVM?

CVE-2018-6335 affects all supported versions of HHVM (3.25.2, 3.24.6, and 3.21.10 and below) when using the proxygen server to handle HTTP2 requests.

3

What is the severity of CVE-2018-6335?

The severity of CVE-2018-6335 is rated as high with a CVSS score of 7.5.

4

How can I fix CVE-2018-6335?

To fix CVE-2018-6335, it is recommended to upgrade HHVM to version 3.25.3 or later, which contains the fix for this vulnerability.

5

Are there any references for CVE-2018-6335?

Yes, you can find more information about CVE-2018-6335 in the following references: [GitHub commit](https://github.com/facebook/hhvm/commit/4cb57dd753a339654ca464c139db9871fe961d56) and [HHVM blog post](https://hhvm.com/blog/2018/05/04/hhvm-3.25.3.html).

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