What is CVE-2021-20473?

CVE-2021-20473 is a medium-severity vulnerability in IBM Sterling File Gateway, classified under Insufficient Session Expiration. CVSS score: 6.5/10. Published 2021-10-07.

How severe is CVE-2021-20473?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in IBM Sterling File Gateway

CVE-2021-20473

IBM Sterling File Gateway User Interface 2.2.0.0 through 6.1.1.0 does not invalidate session after logout which could allow an authenticated user to impersonate another user on the system. IBM X-Force ID: 196944.

Published 2021-10-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (38.9th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

IBM Sterling File Gateway — versions 2.2.0.0, 6.0.0.0, 5.2.6.5_3
IBM Sterling File Gateway

Weakness classification (CWE)

CWE-613 — Insufficient Session Expiration

References

www.ibm.com/support/pages/node/6496785 (Patch, Vendor Advisory)
exchange.xforce.ibmcloud.com/vulnerabilities/196944 (VDB Entry, vdb-entry, Vendor Advisory)

Frequently asked questions

What is CVE-2021-20473?: CVE-2021-20473 is a medium-severity vulnerability in IBM Sterling File Gateway, classified under Insufficient Session Expiration. CVSS score: 6.5/10. Published 2021-10-07.
How severe is CVE-2021-20473?: Medium severity. CVSS v3 base score is 6.5 out of 10.