What is CVE-2020-36405?

CVE-2020-36405 is a high-severity vulnerability in Keystone-Engine Keystone Engine, classified under Use After Free. CVSS score: 7.8/10. Published 2021-07-01.

How severe is CVE-2020-36405?

High severity. CVSS v3 base score is 7.8 out of 10.

Use After Free in Keystone-Engine Keystone Engine

CVE-2020-36405

Keystone Engine 0.9.2 has a use-after-free in llvm_ks::X86Operand::getToken.

Vulnerability class: Use-After-Free

Published 2021-07-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (64.5th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Keystone-Engine Keystone Engine — versions 0.9.2
Linux Kernel

Weakness classification (CWE)

CWE-416 — Use After Free

References

github.com/keystone-engine/keystone/releases (Third Party Advisory, Release Notes)
bugs.chromium.org/p/oss-fuzz/issues/detail (Exploit, Patch, Third Party Advisory, Issue Tracking)
github.com/google/oss-fuzz-vulns/blob/main/vulns/keystone/OSV-2020-789.yaml (Technical Description)

Frequently asked questions

What is CVE-2020-36405?: CVE-2020-36405 is a high-severity vulnerability in Keystone-Engine Keystone Engine, classified under Use After Free. CVSS score: 7.8/10. Published 2021-07-01.
How severe is CVE-2020-36405?: High severity. CVSS v3 base score is 7.8 out of 10.