CVE-2018-6335

Description

A Malformed h2 frame can cause 'std::out_of_range' 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.

Categories

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.60%
Vendor Advisory hhvm.com
Affected: Facebook HHVM
Published at:
Updated at:

References

Link Tags
https://hhvm.com/blog/2018/05/04/hhvm-3.25.3.html vendor advisory
https://github.com/facebook/hhvm/commit/4cb57dd753a339654ca464c139db9871fe961d56 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2018-6335?
CVE-2018-6335 has been scored as a high severity vulnerability.
How to fix CVE-2018-6335?
To fix CVE-2018-6335, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-6335 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-6335 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2018-6335?
CVE-2018-6335 affects Facebook HHVM.
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