Out-of-bounds Read in Facebook Hhvm

CVE-2020-1918

In-memory file operations (ie: using fopen on a data URI) did not properly restrict negative seeking, allowing for the reading of memory prior to the in-memory buffer. This issue affects HHVM versions prior to 4.56.3, all versions between…

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:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-1918?
CVE-2020-1918 is a high-severity vulnerability in Facebook Hhvm, classified under Buffer Under-read. CVSS score: 7.5/10. Published 2021-03-10.
How severe is CVE-2020-1918?
High severity. CVSS v3 base score is 7.5 out of 10.