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TI-2020-01827 Aliases CVE-2020-1900GHSA-g7r3-m2h7-28vw

Use after free in Meta HHVM

Priority MEDIUM 45CWE-416Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

When unserializing an object with dynamic properties HHVM needs to pre-reserve the full size of the dynamic property array before inserting anything into it. Otherwise the array might resize, invalidating previously stored references. This pre-reservation was not occurring in HHVM prior to v4.32.3, between versions 4.33.0 and 4.56.0, 4.57.0, 4.58.0, 4.58.1, 4.59.0, 4.60.0, 4.61.0, 4.62.0.

Why it matters now

EPSS 0.01384 72nd percentileScored 2026-11-07
Fix Fixed HHVM (Facebook): 4.62.1, 4.61.1, 4.60.1 +5

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MetaHHVM4.62.0; 4.61.0; 4.60.0; 4.59.0; 4.58.0 and later; 4.57.0; 4.33.0 and later; before 4.32.34.62.1, 4.61.1, 4.60.1, 4.59.1, 4.58.2, 4.57.1, 4.56.1, 4.32.3Patch availableCNA
  • HHVM VendorMeta Affected 4.62.0; 4.61.0; 4.60.0; 4.59.0; 4.58.0 and later; 4.57.0; 4.33.0 and later; before 4.32.3 Fixed in 4.62.1, 4.61.1, 4.60.1, 4.59.1, 4.58.2, 4.57.1, 4.56.1, 4.32.3 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:a:facebook:hhvm:*:*:*:*:*:*:*:*before 4.32.3; 4.33.0 to before 4.56.1VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.57.0:*:*:*:*:*:*:*4.57.0VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.58.0:*:*:*:*:*:*:*4.58.0VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.58.1:*:*:*:*:*:*:*4.58.1VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.59.0:*:*:*:*:*:*:*4.59.0VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.60.0:*:*:*:*:*:*:*4.60.0VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.61.0:*:*:*:*:*:*:*4.61.0VulnerableMeta
cpe:2.3:a:facebook:hhvm:4.62.0:*:*:*:*:*:*:*4.62.0VulnerableMeta
  • cpe:2.3:a:facebook:hhvm:*:*:*:*:*:*:*:* Versions before 4.32.3; 4.33.0 to before 4.56.1 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.57.0:*:*:*:*:*:*:* Versions 4.57.0 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.58.0:*:*:*:*:*:*:* Versions 4.58.0 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.58.1:*:*:*:*:*:*:* Versions 4.58.1 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.59.0:*:*:*:*:*:*:* Versions 4.59.0 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.60.0:*:*:*:*:*:*:* Versions 4.60.0 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.61.0:*:*:*:*:*:*:* Versions 4.61.0 Vulnerable ·Meta
  • cpe:2.3:a:facebook:hhvm:4.62.0:*:*:*:*:*:*:* Versions 4.62.0 Vulnerable ·Meta

Remediation

  • Fix · CNA HHVM (Facebook) Fixed in 4.62.1, 4.61.1, 4.60.1, 4.59.1, 4.58.2, 4.57.1, 4.56.1, 4.32.3

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Facebook HHVM 4.32.3, unspecified

    3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW

    Other records, highest priority first

    Show all 3 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-1900
  2. 2026-10-03 Alias added: GHSA-g7r3-m2h7-28vw

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