Description
The unserialize() function supported a type code, "S", which was meant to be supported only for APC serialization. This type code allowed arbitrary memory addresses to be accessed as if they were static StringData objects. 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.
Scores
CVSS v3
7.5
EPSS
0.0036
EPSS Percentile
58.2%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Details
CWE
CWE-119
CWE-822
Status
published
Products (8)
facebook/hhvm
4.57.0
facebook/hhvm
4.58.0
facebook/hhvm
4.58.1
facebook/hhvm
4.59.0
facebook/hhvm
4.60.0
facebook/hhvm
4.61.0
facebook/hhvm
4.62.0
facebook/hhvm
< 4.32.3
Published
Mar 11, 2021
Tracked Since
Feb 18, 2026