CVE-2018-20916
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 · uneditedcPanel before 70.0.23 allows Stored XSS via a WHM Edit MX Entry (SEC-370).
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 · moderate confidenceA stored cross-site scripting (XSS) vulnerability exists in cPanel's WHM (Web Host Manager) interface, specifically in the Edit MX Entry feature, affecting versions prior to 70.0.23. An authenticated attacker with WHM access can inject malicious JavaScript code into MX entry fields that gets stored and executed in the browsers of other users viewing these entries.
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< 70.0.23CVSS 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
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/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.
-
Verify cPanel/WHM versionLog into WHM and check the version displayed in the footer, or run 'whmapi1 version' via command lineAffected if The installed version is lower than 70.0.23 (for example, 70.0.22, 68.x, etc.)
-
Confirm WHM access is enabledVerify that the WHM interface is accessible and check if untrusted users have WHM login privilegesAffected if WHM is exposed to users who are not trusted administrators
-
Check for MX entry configuration accessNavigate to WHM > DNS Functions > Edit MX Entry or use 'whmapi1 list_mx_entries' via command line to review existing MX recordsAffected if MX entry editing is accessible and entries exist in the system
-
Inspect MX entries for suspicious contentReview all MX entries for any unexpected characters, script tags, or encoded JavaScript payloads in the destination fields (such as <script>, javascript:, onerror=, etc.)Affected if Any MX entry contains HTML or JavaScript code that was not intentionally configured by an administrator
You are affected if your cPanel version is below 70.0.23 and your WHM Edit MX Entry feature contains unexpected script content that could execute in user browsers.
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 data70.0.23
Update cPanel to version 70.0.23 or later to apply the patch. Until the update is applied, restrict WHM access to trusted administrators only and monitor for suspicious activity.
- Consultation2.0 h
- Implementation3.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-20916 — 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-2018-20916 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
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.
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.
- 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