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TI-2018-04660 Aliases CVE-2018-6335GHSA-3j37-x46m-f23g

Uncontrolled resource consumption in Meta HHVM

Priority MEDIUM 42CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-400.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01469 73rd percentileScored 2026-11-07
Fix Fixed HHVM (Facebook): 3.21.11

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MetaHHVM3.25.3; 3.25.0; 3.24.7; 3.22.0; 3.21.11; before 3.21.113.21.11Patch availableCNA
  • HHVM VendorMeta Affected 3.25.3; 3.25.0; 3.24.7; 3.22.0; 3.21.11; before 3.21.11 Fixed in 3.21.11 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:facebook:hhvm:*:*:*:*:*:*:*:*up to 3.21.10VulnerableMeta
cpe:2.3:a:facebook:hhvm:3.24.6:*:*:*:*:*:*:*3.24.6VulnerableMeta
cpe:2.3:a:facebook:hhvm:3.25.2:*:*:*:*:*:*:*3.25.2VulnerableMeta
  • cpe:2.3:a:facebook:hhvm:*:*:*:*:*:*:*:* Versions up to 3.21.10 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:3.24.6:*:*:*:*:*:*:* Versions 3.24.6 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:3.25.2:*:*:*:*:*:*:* Versions 3.25.2 Vulnerable ·Meta

Remediation

  • Fix · CNA HHVM (Facebook) Fixed in 3.21.11

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-6335
  2. 2026-10-03 Alias added: GHSA-3j37-x46m-f23g

References

Patch 1

Advisory 1

  • TI-2018-04659 Improper input validation in Meta HHVM CVSS 3.1CRITICAL 9.8
  • TI-2022-17147 Broken or risky cryptographic algorithm in Meta HHVM CVSS 3.1CRITICAL 9.8
  • TI-2019-08934 Memory corruption in Meta HHVM CVSS 3.1CRITICAL 9.8
  • TI-2021-06352 Heap-based buffer overflow in Meta folly CVSS 3.1CRITICAL 9.8
  • TI-2019-08935 An invalid free in mb_detect_order can cause the application to crash or potentially… CVSS 3.1CRITICAL 9.8
  • TI-2016-05898 Integer overflow in bcmath in Facebook HHVM before 3.15.0 allows attackers to have… CVSS 3.0CRITICAL 9.8
See all 39 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences