Resource exhaustion in Facebook Hhvm

CVE-2018-6335

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.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.015 (72.7th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 72.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2018-6335: held from 0.015 to 0.015.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2018-6335?
CVE-2018-6335 is a high-severity vulnerability in Facebook Hhvm, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2018-12-31.
How severe is CVE-2018-6335?
High severity. CVSS v3 base score is 7.5 out of 10.