What is CVE-2021-20745?

CVE-2021-20745 is a high-severity vulnerability in Inkdrop, classified under OS Command Injection. CVSS score: 7.8/10. Published 2021-06-28.

How severe is CVE-2021-20745?

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

RCE in Inkdrop

CVE-2021-20745

Inkdrop versions prior to v5.3.1 allows an attacker to execute arbitrary OS commands on the system where it runs by loading a file or code snippet containing an invalid iframe into Inkdrop.

Vulnerability class: Command Injection (OS Command Injection)

Published 2021-06-28 · 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: 0.010 (60.4th percentile), scored 2026-10-05.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 60.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Inkdrop
Takuya Matsuyama Inkdrop — versions versions prior to v5.3.1

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

www.inkdrop.app/ (Product, Vendor Advisory)
docs.inkdrop.app/releases/5.3.1 (Release Notes, Vendor Advisory)
jvn.jp/en/jp/JVN29949691/index.html (Third Party Advisory)

Frequently asked questions

What is CVE-2021-20745?: CVE-2021-20745 is a high-severity vulnerability in Inkdrop, classified under OS Command Injection. CVSS score: 7.8/10. Published 2021-06-28.
How severe is CVE-2021-20745?: High severity. CVSS v3 base score is 7.8 out of 10.