# CVE-2021-20113: Information disclosure in TCExam

> Attackers can enumerate registered user email addresses by observing distinct error messages during password reset requests in TCExam.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:** 29 Jul 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-f452-fg56-fx5m

## What is CVE-2021-20113?

CVE-2021-20113 is a medium-severity vulnerability in TCExam, published on 29 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An exposure of sensitive information vulnerability exists in TCExam <= 14.8.1. If a password reset request was made for an email address that was not registered with a user then we would be presented with an ‘unknown email’ error. If an email is given that is registered with a user then this error will not appear. A malicious actor could abuse this to enumerate the email addresses of

Weakness: CWE-203 (Observable Discrepancy)

## Which versions are affected by CVE-2021-20113?

It affects 1 product.


Products: Tecnick Tcexam.

## How do I fix CVE-2021-20113?

No fix has been published for CVE-2021-20113 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20113 being exploited?

There is no known exploitation of CVE-2021-20113 in the wild and no public exploit code.

## Other vulnerabilities in TCExam

- [CVE-2021-20114](https://insights.sbomify.com/CVE-2021-20114/): Information disclosure in TCExam (high 7.5)
- [CVE-2020-5745](https://insights.sbomify.com/CVE-2020-5745/): Cross-site request forgery in TCExam (high 7.4)
- [CVE-2012-4237](https://insights.sbomify.com/CVE-2012-4237/): SQL injection in n/a (medium 6.8)
- [CVE-2010-2153](https://insights.sbomify.com/CVE-2010-2153/): File upload in n/a (medium 6.8)
- [CVE-2023-6554](https://insights.sbomify.com/CVE-2023-6554/): Missing authorisation in TCExam (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20113 and fix it if it is affected.

What it is: CVE-2021-20113 is a medium-severity vulnerability in TCExam, published on 29 Jul 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-2021-20113 in the wild and no public exploit code.

Affected product: TCExam. 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-2021-20113/ (Markdown: https://insights.sbomify.com/CVE-2021-20113/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20113
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20113
- OSV: https://osv.dev/vulnerability/CVE-2021-20113

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20113/
Summaries are generated and may contain mistakes; the official description above is the record.