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TI-2020-01825 Aliases CVE-2020-1898GHSA-86q4-p3xc-6m2h

Uncontrolled recursion in Meta HHVM

Priority LOW 35CWE-674Published · 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 · NVD. Fix status from CNA. Impact type from CWE-674.

Summary

The fb_unserialize function did not impose a depth limit for nested deserialization. That meant a maliciously constructed string could cause deserialization to recurse, leading to stack exhaustion. This issue affected 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 0.01211 68th 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-2020-1898
  2. 2026-10-03 Alias added: GHSA-86q4-p3xc-6m2h

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