Buffer overflow in Facebook Hhvm

CVE-2019-11929

Insufficient boundary checks when formatting numbers in number_format allows read/write access to out-of-bounds memory, potentially leading to remote code execution. This issue affects HHVM versions prior to 3.30.10, all versions between 4.0.0 and 4.8.5, all versions between 4.9.0 and 4.18.2, and versions 4.19.0, 4.19.1, 4.20.0, 4.20.1, 4.20.2, 4.21.0, 4.22.0, 4.23.0.

Vulnerability class: Buffer Overflow

EPSS: 0.040 (89.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-11929?
CVE-2019-11929 is a critical-severity vulnerability in Facebook Hhvm, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2019-10-02.
How severe is CVE-2019-11929?
Critical severity. CVSS v3 base score is 9.8 out of 10.