CVE-2018-4300
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 · uneditedThe session cookie generated by the CUPS web interface was easy to guess on Linux, allowing unauthorized scripted access to the web interface when the web interface is enabled. This issue affected versions prior to v2.2.10.
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 confidenceThe CUPS web interface generated session cookies using a predictable or easily guessable algorithm, allowing attackers to craft valid session tokens through brute-force or calculation. This enabled unauthorized scripted access to the web interface without authentication when the web interface was enabled.
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< 2.2.10CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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 checksWork through these to decide whether this CVE applies to you.
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Identify installed CUPS versionRun 'cups-config --version' or 'dpkg -l cups' (Debian) / 'rpm -q cups' (RHEL) to retrieve the installed CUPS package versionAffected if The version number is lower than 2.2.10 (e.g., 2.2.9, 2.2.8, 2.2.7, etc.)
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Confirm CUPS service is runningCheck if the cupsd daemon is active using 'systemctl status cups' or 'ps aux | grep cupsd'Affected if The CUPS service is running and the process is active on the system
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Verify web interface is enabledCheck if cupsd is listening on a network port (typically port 631) by running 'netstat -tlnp | grep 631' or 'ss -tlnp | grep 631', or inspect /etc/cups/cupsd.conf for 'Listen' directives that bind to network interfacesAffected if The CUPS web interface is bound to a network interface (Listen localhost:631 or Listen *:631) and accessible over the network
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Test web interface accessibilityAttempt to access the CUPS web interface remotely or locally via HTTP to port 631 (e.g., 'curl http://localhost:631')Affected if The web interface responds and allows unauthenticated access to session cookies
The system is affected if CUPS version is below 2.2.10 AND the CUPS web interface is enabled and accessible on a network interface, allowing attackers to potentially brute-force or calculate valid session cookies.
Generated from the published advisory. Verify against your own configuration.
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 data2.2.10
Upgrade CUPS to version 2.2.10 or later. If the web interface is not required, disable it to eliminate the attack surface.
- Consultation1.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-4300 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2018-4300 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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
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