# CVE-2021-1572: ConfD CLI Secure Shell Server Privilege Escalation Vulnerability

> An authenticated local attacker can escalate privileges to root by exploiting the ConfD CLI SSH server's SFTP service when enabled.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 Aug 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-jjcm-mvqj-g3mq

## What is CVE-2021-1572?

CVE-2021-1572 is a high-severity vulnerability in Cisco ConfD, published on 4 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in ConfD could allow an authenticated, local attacker to execute arbitrary commands at the level of the account under which ConfD is running, which is commonly root. To exploit this vulnerability, an attacker must have a valid account on an affected device. The vulnerability exists because the affected software incorrectly runs the SFTP user service at the privilege level of the account that was running when the ConfD built-in Secure Shell (SSH) server for CLI was enabled. If the ConfD built-in SSH server was not enabled, the device is not affected by this vulnerability. An attacker with low-level privileges could exploit this vulnerability by authenticating to an affected device and issuing a series of commands at the SFTP interface. A successful exploit could allow the attacker to elevate privileges to the level of the account under which ConfD is running, which is commonly root. Note: Any user who can authenticate to the built-in SSH server may exploit this vulnerability. By default, all ConfD users have this access if the server is enabled. Software updates that address this vulnerability have been released.

Weakness: CWE-269 (Improper Privilege Management), CWE-266 (Incorrect Privilege Assignment)

## Which versions are affected by CVE-2021-1572?

It affects 2 products.


Products: Cisco Confd, Cisco Network Services Orchestrator.

## How do I fix CVE-2021-1572?

No fix has been published for CVE-2021-1572 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-1572 being exploited?

There is no known exploitation of CVE-2021-1572 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-1572 and fix it if it is affected.

What it is: CVE-2021-1572 is a high-severity vulnerability in Cisco ConfD, published on 4 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-1572 in the wild and no public exploit code.

Affected product: Cisco ConfD. 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-2021-1572/ (Markdown: https://insights.sbomify.com/CVE-2021-1572/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-1572
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-1572
- OSV: https://osv.dev/vulnerability/CVE-2021-1572

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-1572/
Summaries are generated and may contain mistakes; the official description above is the record.