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Hospitality Opera 5Application · Oracle

CVE-2025-21547

CRITICAL · 9.1 CVSS v3.1 Published 2025-01-21
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
Vulnerability in the Oracle Hospitality OPERA 5 product of Oracle Hospitality Applications (component: Opera Servlet). Supported versions that are affected are 5.6.19.20, 5.6.25.8, 5.6.26.6 and 5.6.27.1. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Oracle Hospitality OPERA 5. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle Hospitality OPERA 5 accessible data and unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Oracle Hospitality OPERA 5. CVSS 3.1 Base Score 9.1 (Confidentiality and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H).

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

Unauthenticated remote vulnerability in the Opera Servlet component of Oracle Hospitality OPERA 5 property management software. Attackers with network access via HTTP can exploit this flaw without credentials to gain unauthorized access to critical or all accessible data, and also cause complete denial of service.

MitigationApply Oracle Critical Patch Updates for the affected versions (5.6.19.20, 5.6.25.8, 5.6.26.6, 5.6.27.1). If immediate patching is not possible, restrict network exposure of the Opera Servlet endpoints to trusted networks or implement additional authentication layers at the network perimeter.

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
Hospitality Opera 5Application
Affected:= 5.6.19.20= 5.6.25.8= 5.6.26.6= 5.6.27.1

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
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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 Oracle OPERA 5 is installed
    Check for OPERA 5 processes or services running on the system. Look for process names like 'opera', 'opera5', or check Windows Services/Unix init scripts for OPERA-related services.
    Affected if OPERA 5 processes or services are found running on the host
  2. Determine OPERA 5 version
    Locate the OPERA 5 installation directory and check version files, about dialogs, or use OPERA admin utilities to query the installed version number.
    Affected if Installed version matches 5.6.19.20, 5.6.25.8, 5.6.26.6, or 5.6.27.1
  3. Verify Opera Servlet HTTP interface is exposed
    Identify the HTTP listener port for the Opera Servlet component (commonly ports 8080, 8000, or custom OPERA ports). Check if the port is open and responding using netstat, nmap, or by accessing the URL.
    Affected if HTTP port serving the Opera Servlet is open and accessible
  4. Check network accessibility of HTTP interface
    Determine if the OPERA HTTP port is bound to all interfaces (0.0.0.0) or directly accessible from external networks. Use network scanning tools or review firewall rules to assess exposure.
    Affected if The Opera Servlet HTTP port is reachable from untrusted networks or the internet without authentication

A user is affected if OPERA 5 version 5.6.19.20, 5.6.25.8, 5.6.26.6, or 5.6.27.1 is running with the Opera Servlet HTTP interface exposed to the network.

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

Apply Oracle Critical Patch Updates for the affected versions (5.6.19.20, 5.6.25.8, 5.6.26.6, 5.6.27.1). If immediate patching is not possible, restrict network exposure of the Opera Servlet endpoints to trusted networks or implement additional authentication layers at the network perimeter.

Fix this in Hospitality Opera 5 Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA4.0 h
40.0 hours of engineering $7,000
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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-2025-21547 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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