# CVE-2021-40128: Cisco Webex Meetings Email Content Injection Vulnerability

> An attacker can send account activation emails with tampered links, directing users to attacker-controlled websites via insufficient parameter validation.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 Nov 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-f5wr-xjgr-jhq9

## What is CVE-2021-40128?

CVE-2021-40128 is a medium-severity vulnerability in Cisco Webex Meetings, published on 4 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the account activation feature of Cisco Webex Meetings could allow an unauthenticated, remote attacker to send an account activation email with an activation link that points to an arbitrary domain. This vulnerability is due to insufficient validation of user-supplied parameters. An attacker could exploit this vulnerability by sending a crafted HTTP request to the account activation page of Cisco Webex Meetings. A successful exploit could allow the attacker to send to any recipient an account activation email that contains a tampered activation link, which could direct the user to an attacker-controlled website.

Weakness: CWE-183 (Permissive List of Allowed Inputs)

## Which versions are affected by CVE-2021-40128?

It affects 1 product.


Products: Cisco Webex Meetings.

## How do I fix CVE-2021-40128?

No fix has been published for CVE-2021-40128 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40128 being exploited?

There is no known exploitation of CVE-2021-40128 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Webex Meetings

- [CVE-2017-12368](https://insights.sbomify.com/CVE-2017-12368/): Memory corruption in Cisco WebEx Recording Format and Advanced Recording Format Players (critical 9.6)
- [CVE-2017-12369](https://insights.sbomify.com/CVE-2017-12369/): Memory corruption in Cisco WebEx Recording Format and Advanced Recording Format Players (critical 9.6)
- [CVE-2017-12370](https://insights.sbomify.com/CVE-2017-12370/): Memory corruption in Cisco WebEx Recording Format and Advanced Recording Format Players (critical 9.6)
- [CVE-2017-12371](https://insights.sbomify.com/CVE-2017-12371/): Memory corruption in Cisco WebEx Recording Format and Advanced Recording Format Players (critical 9.6)
- [CVE-2017-12372](https://insights.sbomify.com/CVE-2017-12372/): Memory corruption in Cisco WebEx Recording Format and Advanced Recording Format Players (critical 9.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40128 and fix it if it is affected.

What it is: CVE-2021-40128 is a medium-severity vulnerability in Cisco Webex Meetings, published on 4 Nov 2021. 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-2021-40128 in the wild and no public exploit code.

Affected product: Cisco Webex Meetings. 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-2021-40128/ (Markdown: https://insights.sbomify.com/CVE-2021-40128/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40128
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40128
- OSV: https://osv.dev/vulnerability/CVE-2021-40128

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40128/
Summaries are generated and may contain mistakes; the official description above is the record.