dbcve.org
ZncApplication

CVE-2009-0759

MEDIUM · 6.5 CVSS v2.0 Published 2009-03-03
Fix available
A fix is available. Upgrade to after 0.062 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable 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
Multiple CRLF injection vulnerabilities in webadmin in ZNC before 0.066 allow remote authenticated users to modify the znc.conf configuration file and gain privileges via CRLF sequences in the quit message and other vectors.

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

CRLF injection vulnerability in ZNC webadmin before version 0.066 allows remote authenticated users to inject carriage return and line feed characters into parameters like the quit message. This enables manipulation of the znc.conf configuration file and potential privilege escalation.

MitigationUpgrade ZNC to version 0.066 or later to patch the CRLF injection vulnerability in webadmin.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
ZncApplication
Affected:<= 0.062= 0.056= 0.058

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
Authentication
Single
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:L/Au:S/C:P/I:P/A:P

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. Determine installed ZNC version
    Run `znc --version` or check your package manager for the installed znc package version
    Affected if The version is 0.056, 0.058, or any version 0.062 or lower
  2. Verify webadmin module is loaded
    Check znc.conf for a LoadModule line containing 'webadmin', or run `znc --listmodules` to see loaded modules
    Affected if The webadmin module is loaded and accessible
  3. Confirm remote access to webadmin
    Check znc.conf for the webadmin Listen clause - look for Listen port configurations that bind to 0.0.0.0 or non-localhost addresses, rather than 127.0.0.1 only
    Affected if Webadmin is accessible from remote hosts (not bound to localhost only)
  4. Check if remote user authentication exists
    Review znc.conf for defined users with valid passwords, or check if any webadmin users have login credentials configured
    Affected if Remote authenticated users exist in the ZNC configuration

You are affected if ZNC version is 0.056, 0.058, or 0.062 or lower AND the webadmin module is loaded and accessible to remote authenticated users.

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
Upgrade available Upgrade to a release after 0.062
Interim mitigation

Upgrade ZNC to version 0.066 or later to patch the CRLF injection vulnerability in webadmin.

Fix this in Znc Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2009-0759 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2009-0759 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data