CWE-1236Weakness · CWE-1236

CVE-2021-47901

CRITICAL · 9.8 CVSS v3.1 Published 2026-01-27
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Dirsearch 0.4.1 contains a CSV injection vulnerability when using the --csv-report flag that allows attackers to inject formulas through redirected endpoints. Attackers can craft malicious server redirects with comma-separated paths containing Excel formulas to manipulate the generated CSV report.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Dirsearch 0.4.1 is vulnerable to CSV injection via the --csv-report flag. When processing server redirects containing comma-separated paths with embedded Excel formula characters (=, +, -, @), the tool writes these directly to the CSV output without sanitization. When opened in spreadsheet applications, the formulas execute, potentially leading to arbitrary code execution on the victim's machine.

MitigationSanitize all CSV output by escaping or filtering formula-initiating characters (=, +, -, @, tab, CR, LF) before writing to the CSV report, or use a CSV library with built-in formula injection protection.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm Dirsearch version
    Run 'dirsearch --version' or check the installed package version via pip (pip show dirsearch) or your package manager
    Affected if Version is 0.4.1 specifically, or falls within any 0.4.x release prior to fix
  2. Identify CSV report usage
    Review command history, scripts, or running processes for dirsearch invocations containing the '--csv-report' or '-r' flag (if csv-report is configured)
    Affected if The --csv-report flag was used to generate CSV output
  3. Locate generated CSV reports
    Find CSV files created by dirsearch (typically named with timestamps or specified via --csv-target) and inspect them for formula characters
    Affected if CSV files exist and contain unescaped characters: =, +, -, @, tab, CR, or LF at the start of any cell value
  4. Check server redirect handling
    Review dirsearch output logs or captured network traffic for HTTP 3xx redirects containing comma-separated paths
    Affected if Server redirects with paths containing special characters (=, +, -, @) were processed and written to CSV output

A user is affected if they ran Dirsearch version 0.4.1 with the --csv-report flag and the resulting CSV was later opened in a spreadsheet application without manual sanitization of formula characters.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Sanitize all CSV output by escaping or filtering formula-initiating characters (=, +, -, @, tab, CR, LF) before writing to the CSV report, or use a CSV library with built-in formula injection protection.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-47901 in production — separate from our analysis above.

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What this is

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