Vulnerability in Facebook Hhvm

CVE-2020-1898

The fb_unserialize function did not impose a depth limit for nested deserialization. That meant a maliciously constructed string could cause deserialization to recurse, leading to stack exhaustion. 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.

EPSS: 0.012 (65.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-1898?
CVE-2020-1898 is a high-severity vulnerability in Facebook Hhvm, classified under Uncontrolled Recursion. CVSS score: 7.5/10. Published 2021-03-11.
How severe is CVE-2020-1898?
High severity. CVSS v3 base score is 7.5 out of 10.