Vulnerability · Published Mar 11, 2021 · Assigned by facebook

CVE-2020-1899

High 7.5

In plain English

A high-severity security flaw in HHVM from Facebook. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.2% (higher than 69% of all known vulnerabilities).

Severity (CVSS NVD)7.5High
Exploit odds (30 days)1.2%top 31.2% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

VendorProductVersions
Facebook HHVM 4.62.04.61.04.60.04.59.0

Weakness: CWE-822

References