What is CVE-2021-20496?

CVE-2021-20496 is a medium-severity vulnerability in Docker, classified under Improper Input Validation. CVSS score: 4.9/10. Published 2021-07-15.

How severe is CVE-2021-20496?

Medium severity. CVSS v3 base score is 4.9 out of 10.

Improper input validation in Docker

CVE-2021-20496

IBM Security Verify Access Docker 10.0.0 could allow an authenticated user to bypass input due to improper input validation. IBM X-Force ID: 197966.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2021-07-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.006 (49.1th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Docker
IBM Security Verify Access — versions 10.0.0
IBM Security Verify Access Docker — versions 10.0.0

Weakness classification (CWE)

CWE-20 — Improper Input Validation

References

www.ibm.com/support/pages/node/6471895 (Patch, Vendor Advisory)
exchange.xforce.ibmcloud.com/vulnerabilities/197966 (VDB Entry, vdb-entry, Vendor Advisory)

Frequently asked questions

What is CVE-2021-20496?: CVE-2021-20496 is a medium-severity vulnerability in Docker, classified under Improper Input Validation. CVSS score: 4.9/10. Published 2021-07-15.
How severe is CVE-2021-20496?: Medium severity. CVSS v3 base score is 4.9 out of 10.