OS Command InjectionWeakness · CWE-78

CVE-2026-8500

CRITICAL · 9.8 CVSS v3.1 Published 2026-05-13
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
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
Web::Passwd versions through 0.03 for Perl is vulnerable to RCE. Web::Passwd is a small CGI application for managing htpasswd files using the htpasswd command. The user parameter is not validated or escaped, and is used as the last argument on the command line, allowing for command injection.

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

Web::Passwd versions 0.03 and earlier contain a command injection vulnerability in the user parameter handling. The user-supplied input is passed directly as the final argument to the htpasswd command line without validation or escaping, allowing an attacker to inject arbitrary shell commands.

MitigationImplement strict input validation for the user parameter, using whitelisting of allowed characters (alphanumeric only), or employ proper shell escaping mechanisms when constructing the htpasswd command. Consider refactoring to use htpasswd library functions instead of invoking the binary.

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. Identify if Web::Passwd is installed
    Check your Perl library installation directory or look for Web::Passwd in your project's dependency list (e.g., check cpanfile, Makefile.PL, or run 'perldoc -l Web::Passwd')
    Affected if Web::Passwd is not found in your environment
  2. Determine the installed version of Web::Passwd
    Run 'perl -MWeb::Passwd -e "print $Web::Passwd::VERSION"' or check the version listed in your installed module files
    Affected if The version is 0.03 or earlier
  3. Locate the Web::Passwd source code
    Find the installed Web::Passwd.pm file (typically in your Perl @INC path) and examine the code that handles the user parameter, looking for system calls or backtick execution invoking htpasswd
    Affected if The code passes the user parameter directly to htpasswd without sanitization
  4. Identify if the vulnerable code path is reachable
    Review your application code that uses Web::Passwd to determine if user input is passed to the affected parameter without prior validation
    Affected if User-supplied input reaches the Web::Passwd user parameter handler
  5. Verify htpasswd is invoked by your Web::Passwd usage
    Search the Web::Passwd code for exec, system, or backtick calls that invoke the htpasswd binary, and confirm your configuration triggers these calls
    Affected if Your Web::Passwd usage triggers htpasswd command execution with user-controlled input

You are affected if Web::Passwd version 0.03 or earlier is installed and your application passes unsanitized user input to the vulnerable parameter that gets passed to the htpasswd command line.

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

Implement strict input validation for the user parameter, using whitelisting of allowed characters (alphanumeric only), or employ proper shell escaping mechanisms when constructing the htpasswd command. Consider refactoring to use htpasswd library functions instead of invoking the binary.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA3.0 h
17.0 hours of engineering $3,020
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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-2026-8500 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
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  • Version or environment caveats, and links to real fixes
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