# CVE-2021-21511: Missing authorization in Avamar

> A remote low-privileged attacker can exploit improper authorization in the web UI to read or modify other users' backup data.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Feb 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-2gr2-xjj5-q4ff

## What is CVE-2021-21511?

CVE-2021-21511 is a high-severity missing authorization vulnerability in Dell Avamar, published on 15 Feb 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Dell EMC Avamar Server, versions 19.3 and 19.4 contain an Improper Authorization vulnerability in the web UI. A remote low privileged attacker could potentially exploit this vulnerability, to gain unauthorized read or modification access to other users' backup data.

Weakness: CWE-285 (Improper Authorization)

## Which versions are affected by CVE-2021-21511?

It affects 2 products.


Products: Dell Emc Avamar Server, Dell Emc Integrated Data Protection Appliance.

## How do I fix CVE-2021-21511?

No fix has been published for CVE-2021-21511 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-21511 being exploited?

There is no known exploitation of CVE-2021-21511 in the wild and no public exploit code.

## Other vulnerabilities in Dell Avamar

- [CVE-2020-29493](https://insights.sbomify.com/CVE-2020-29493/): SQL injection in Avamar (critical 10.0)
- [CVE-2020-29495](https://insights.sbomify.com/CVE-2020-29495/): Command injection in Avamar (critical 10.0)
- [CVE-2020-5341](https://insights.sbomify.com/CVE-2020-5341/): Deserialization in Avamar Virtual Edition (critical 9.8)
- [CVE-2020-29494](https://insights.sbomify.com/CVE-2020-29494/): Path traversal in Avamar (high 8.7)
- [CVE-2019-3752](https://insights.sbomify.com/CVE-2019-3752/): XML external entity in Avamar (high 8.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-21511 and fix it if it is affected.

What it is: CVE-2021-21511 is a high-severity missing authorization vulnerability in Dell Avamar, published on 15 Feb 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-21511 in the wild and no public exploit code.

Affected product: Dell Avamar. 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-2021-21511/ (Markdown: https://insights.sbomify.com/CVE-2021-21511/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21511
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21511
- OSV: https://osv.dev/vulnerability/CVE-2021-21511

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-21511/
Summaries are generated and may contain mistakes; the official description above is the record.