CVE-2020-1900 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://hhvm.com/blog/2020/06/30/security-update.html https://github.com/facebook/hhvm/commit/c1c4bb0cf9e076aafaf4ff3515556ef9faf906f3

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8