# CVE-2025-21547: Denial of service in Oracle Hospitality OPERA 5

> Unauthenticated attackers can cause denial of service and access critical data in Oracle Hospitality OPERA 5 via HTTP.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Jan 2025
- **Updated:** 18 Mar 2025
- **Also known as:** GHSA-wcg3-v8j6-c8gg

## What is CVE-2025-21547?

CVE-2025-21547 is a critical denial of service vulnerability in Oracle Hospitality OPERA 5, published on 21 Jan 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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).

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2025-21547?

It affects 1 product.


Products: Oracle Hospitality Opera 5.

## How do I fix CVE-2025-21547?

No fix has been published for CVE-2025-21547 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-21547 being exploited?

There is no known exploitation of CVE-2025-21547 in the wild and no public exploit code.

## Other vulnerabilities in Oracle Hospitality OPERA 5

- [CVE-2024-21172](https://insights.sbomify.com/CVE-2024-21172/): Auth bypass in Oracle Hospitality OPERA 5 (critical 9.0)
- [CVE-2026-21967](https://insights.sbomify.com/CVE-2026-21967/): Missing authorization in Oracle Hospitality OPERA 5 (high 8.6)
- [CVE-2026-21966](https://insights.sbomify.com/CVE-2026-21966/): Cross-site scripting in Oracle Hospitality OPERA 5 Property Services (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-21547 and fix it if it is affected.

What it is: CVE-2025-21547 is a critical denial of service vulnerability in Oracle Hospitality OPERA 5, published on 21 Jan 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-21547 in the wild and no public exploit code.

Affected product: Oracle Hospitality OPERA 5. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-21547/ (Markdown: https://insights.sbomify.com/CVE-2025-21547/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-21547
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-21547
- OSV: https://osv.dev/vulnerability/CVE-2025-21547

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From sbomify Insights: https://insights.sbomify.com/CVE-2025-21547/
Summaries are generated and may contain mistakes; the official description above is the record.