# CVE-2025-20139: Denial of service in Cisco Enterprise Chat and Email

> Unauthenticated remote attackers can cause a denial of service in Cisco Enterprise Chat and Email by sending malicious requests to chat entry points.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:** 2 Apr 2025
- **Updated:** 2 Apr 2025
- **Also known as:** GHSA-rx2w-x63r-4r67

## What is CVE-2025-20139?

CVE-2025-20139 is a high-severity denial of service vulnerability in Cisco Enterprise Chat and Email, published on 2 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in chat messaging features of Cisco Enterprise Chat and Email (ECE) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.

 This vulnerability is due to improper validation of user-supplied input to chat entry points. An attacker could exploit this vulnerability by sending malicious requests to a messaging chat entry point in the affected application. A successful exploit could allow the attacker to cause the application to stop responding, resulting in a DoS condition. The application may not recover on its own and may need an administrator to manually restart services to recover.

Weakness: CWE-185 (Incorrect Regular Expression)

## Which versions are affected by CVE-2025-20139?

It affects 1 product.


Products: Cisco Enterprise Chat and Email.

## How do I fix CVE-2025-20139?

No fix has been published for CVE-2025-20139 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-20139 being exploited?

There is no known exploitation of CVE-2025-20139 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Enterprise Chat and Email

- [CVE-2024-20484](https://insights.sbomify.com/CVE-2024-20484/): Cisco Enterprise Chat and Email Denial of Service Vulnerability (high 7.5)
- [CVE-2019-1877](https://insights.sbomify.com/CVE-2019-1877/): Cisco Enterprise Chat and Email Attachment Download Vulnerability (medium 6.5)
- [CVE-2025-20310](https://insights.sbomify.com/CVE-2025-20310/): Cisco Enterprise Chat and Email Stored Cross-Site Scripting Vulnerability (medium 6.1)
- [CVE-2022-20631](https://insights.sbomify.com/CVE-2022-20631/): Cisco Enterprise Chat and Email Cross-Site Scripting Vulnerability (medium 6.1)
- [CVE-2022-20632](https://insights.sbomify.com/CVE-2022-20632/): Cisco Enterprise Chat and Email Cross-Site Scripting Vulnerability (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-20139 and fix it if it is affected.

What it is: CVE-2025-20139 is a high-severity denial of service vulnerability in Cisco Enterprise Chat and Email, published on 2 Apr 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-2025-20139 in the wild and no public exploit code.

Affected product: Cisco Enterprise Chat and Email. 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-2025-20139/ (Markdown: https://insights.sbomify.com/CVE-2025-20139/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-20139
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-20139
- OSV: https://osv.dev/vulnerability/CVE-2025-20139

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-20139/
Summaries are generated and may contain mistakes; the official description above is the record.