ExistApplication · Exist Db

CVE-2018-1000823

CRITICAL · 10.0 CVSS v3.1 Published 2018-12-20
Fix available
A fix is available. Upgrade to 5.0.0 or later.
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
exist version <= 5.0.0-RC4 contains a XML External Entity (XXE) vulnerability in XML Parser for REST Server that can result in Disclosure of confidential data, denial of service, SSRF, port scanning.

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 confidence

eXist versions 5.0.0-RC4 and earlier contain an XML External Entity (XXE) vulnerability in the REST Server's XML parser. Attackers can exploit this by submitting malicious XML with external entity references to read confidential files, cause denial of service, perform SSRF, or scan internal ports.

MitigationDisable external entity processing in the REST Server's XML parser configuration, or upgrade to a patched version of eXist.

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
ExistApplication
Affected:< 5.0.0= 5.0.0

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
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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 eXist version
    Locate the eXist installation and check its version (typically found in about file, version metadata, or startup logs)
    Affected if Version is 5.0.0 or any release candidate up to 5.0.0-RC4 (versions below 5.0.0)
  2. Confirm REST Server is in use
    Determine whether the eXist REST Server endpoint is exposed or configured (check server configuration or running services)
    Affected if REST Server is accessible or enabled in the deployment
  3. Check XML parser external entity setting
    Inspect the REST Server XML parser configuration for whether external entity processing is enabled (look for related parser or factory settings in conf/xml)
    Affected if External entity processing is not explicitly disabled in the parser configuration

User is affected if running eXist version 5.0.0 or earlier AND the REST Server is active with default XML parser settings that allow external entity processing.

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.

dbcve · scoped
Upgrade available Upgrade to 5.0.0 or later
Fixed in 5.0.0
Interim mitigation

Disable external entity processing in the REST Server's XML parser configuration, or upgrade to a patched version of eXist.

Recommended fix Moderate confidence

eXist-db 5.1.0 or later

  1. 1. Backup your existing eXist-db installation and database
  2. 2. Download eXist-db version 5.1.0 or later from the official repository (https://github.com/exist-db/exist/releases)
  3. 3. Stop the currently running eXist-db service
  4. 4. Install the new version following the standard upgrade procedure
  5. 5. Restore your database from the backup
  6. 6. Verify the REST server XML parser is functioning correctly
  7. 7. Test that the application works as expected with the new version
Caveat Review release notes for any configuration or API changes between 5.0.x and 5.1.x

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Exist Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,130
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,408.

Scan for this in your stack

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dbcve dependency scanner

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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-2018-1000823 in production — separate from our analysis above.

No notes yet

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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
  • 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