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  4. CVE 2021 4171 calibre web is vulnerable to business logic errors
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Back to active CVEs
Critical · CVSS 9.8CVE-2021-4171GHSA-XP7P-3GX7-J6WX

calibre-web is vulnerable to Business Logic ErrorsCVE-2021-4171

Answer in brief

CVE-2021-4171 records a Critical severity (CVSS 9.8) vulnerability in calibre-web is vulnerable to Business Logic Errors. The current sources do not mark it as known exploited. The current feed maps calibreweb (pip), calibreweb (pypi). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jan 21, 2022Updated Oct 27, 2026Source checked Oct 27, 2026First seen by HOL Oct 27, 2026Material review Oct 27, 2026
Upstream Advisory

Key facts

Risk
Critical · CVSS 9.8
Exploitation
Not marked as known exploited
Affected software
2 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps calibreweb (pip), calibreweb (pypi). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
calibrewebpip<0.6.150.6.15
calibrewebpypi>=0 <0.6.150.6.15

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for calibreweb, calibreweb.
  2. 2Review the reported fix. Update calibreweb to 0.6.15; calibreweb to 0.6.15 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Jan 21, 2022

    Evidence: source:ghsa:source_dates:source-dates:record

  2. Source modified

    Oct 27, 2026

    Evidence: source:ghsa:source_dates:source-dates:record

  3. First seen by HOL

    Oct 27, 2026

Sources and claim methodology

  • GitHub security advisorygithub.com
  • GitHub security advisorygithub.com
  • GitHub security advisorygithub.com
  • Source referencehuntr.dev
  • NVD vulnerability recordnvd.nist.gov
  • Source referencepypi.org
  • GitHub security advisorygithub.com
Upstream source description

calibre-web is vulnerable to Business Logic Errors

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
Not reported
Source
GitHub Security Advisories
Source checked
Oct 27, 2026
References
7 linked sources
Open source record