What’s Vulnerable › Vulnerabilities

CVE-2018-6334

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-12-31 · updated 2026-06-17
• Weakness: CWE-621

Description

Multipart-file uploads call variables to be improperly registered in the global scope. In cases where variables are not declared explicitly before being used this can lead to unexpected behavior. This affects all supported versions of HHVM prior to the patch (3.25.1, 3.24.5, and 3.21.9 and below).

Affected products

• Facebook HHVM: through 3.21.9; from 3.21.10 through 3.24.5; from 3.24.6 through 3.25.1

References

• https://github.com/facebook/hhvm/commit/6937de5544c3eead3466b75020d8382080ed0cff
• https://hhvm.com/blog/2018/03/30/hhvm-3.25.2.html
• https://github.com/facebook/hhvm/commit/6937de5544c3eead3466b75020d8382080ed0cff
• https://hhvm.com/blog/2018/03/30/hhvm-3.25.2.html

Get alerted when CVE-2018-6334 or the next vulnerability affects your stack