What is CVE-2021-4171?

CVE-2021-4171 is a critical-severity vulnerability in Janeczku Calibre-Web, classified under CWE-840. CVSS score: 9.8/10. Published 2022-01-17.

How severe is CVE-2021-4171?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Janeczku Calibre-Web

CVE-2021-4171

calibre-web is vulnerable to Business Logic Errors

Published 2022-01-17 · last modified 2026-06-17.

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.

EPSS exploit prediction

EPSS: 0.014 (71.2th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 71st percentile — 71.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Janeczku Calibre-Web
Janeczku Janeczku/calibre-Web — versions unspecified

Weakness classification (CWE)

CWE-840

References

huntr.dev/bounties/1117f439-133c-4563-afb2-6cd80607bd5c (Exploit, Patch, Third Party Advisory)
github.com/janeczku/calibre-web/commit/3e0d8763c377d2146462811e3e4ccf13f0d312ce (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-4171?: CVE-2021-4171 is a critical-severity vulnerability in Janeczku Calibre-Web, classified under CWE-840. CVSS score: 9.8/10. Published 2022-01-17.
How severe is CVE-2021-4171?: Critical severity. CVSS v3 base score is 9.8 out of 10.