This issue affects HHVM 4.45.0, 4.44.0, 4.43.0, 4.42.0, 4.41.0, 4.40.0, 4.39.0, versions between 4.33.0 and 4.38.0 (inclusive), versions between 4.9.0 and 4.32.0 (inclusive), and versions prior to 4.8.7.
The information has been provided by Vendor
The original article can be found at: https://hhvm.com/blog/2020/02/20/security-update.html
Insufficient boundary checks when decoding JSON in JSON_parser allows read access to out of bounds memory, potentially leading to information leak and DOS
HHVM4.39.0, versions between 4.33.0 and 4.38.0 (inclusive),
HHVM versions between 4.9.0 and 4.32.0 (inclusive),
HHVM versions prior to 4.8.7.