What’s Vulnerable › Vulnerabilities

CVE-2020-1916

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-03-10 · updated 2026-06-17
• Weakness: CWE-122

Description

An incorrect size calculation in ldap_escape may lead to an integer overflow when overly long input is passed in, resulting in an out-of-bounds write. This issue affects HHVM prior to 4.56.2, all versions between 4.57.0 and 4.78.0, 4.79.0, 4.80.0, 4.81.0, 4.82.0, 4.83.0.

Affected products

• Facebook HHVM: before 4.56.2; from 4.57.0 before 4.78.1; 4.79.0, 4.80.0, 4.81.0, 4.82.0, 4.83.0 — fixed in 4.56.2, 4.78.1

How to fix

Upgrade to a fixed version: Facebook HHVM 4.56.2, 4.78.1. Check the vendor advisory for mitigations.

References

• https://github.com/facebook/hhvm/commit/abe0b29e4d3a610f9bc920b8be4ad8403364c2d4
• https://hhvm.com/blog/2020/11/12/security-update.html
• https://github.com/facebook/hhvm/commit/abe0b29e4d3a610f9bc920b8be4ad8403364c2d4
• https://hhvm.com/blog/2020/11/12/security-update.html

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