# CVE-2021-37219: HashiCorp Consul Privilege Escalation Vulnerability

> Non-server agents with valid certificates can access server-only functionality, leading to privilege escalation in HashiCorp Consul.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Sep 2021
- **Updated:** 4 Aug 2024
- **Also known as:** BIT-consul-2021-37219, DEBIAN-CVE-2021-37219, GHSA-ccw8-7688-vqx4, GO-2022-0593, UBUNTU-CVE-2021-37219

## What is CVE-2021-37219?

CVE-2021-37219 is a high-severity vulnerability in n/a, published on 7 Sep 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

HashiCorp Consul and Consul Enterprise 1.10.1 Raft RPC layer allows non-server agents with a valid certificate signed by the same CA to access server-only functionality, enabling privilege escalation. Fixed in 1.8.15, 1.9.9 and 1.10.2.

Weakness: CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2021-37219?

8 open source packages ship an affected version, including github.com/hashicorp/consul and consul. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/hashicorp/consul` | Go | All versions | 1.8.15, 1.9.9, 1.10.2 |
| `github.com/hashicorp/consul` | Go | All versions | 1.8.15 |
| `github.com/hashicorp/consul` | Go | All versions | 1.8.15 |
| `github.com/hashicorp/consul` | Go | From 1.10.1 | 1.10.2 |
| `github.com/hashicorp/consul` | Go | From 1.10.1 | 1.10.2 |
| `github.com/hashicorp/consul` | Go | From 1.9.0 | 1.9.9 |
| `github.com/hashicorp/consul` | Go | From 1.9.0 | 1.9.9 |
| `consul` | Bitnami | All versions | 1.8.15, 1.9.9, 1.10.2 |

Products: Hashicorp Consul.

## How do I fix CVE-2021-37219?

Upgrade github.com/hashicorp/consul to a fixed version for your release line: 1.8.15, 1.9.9 or 1.10.2.

## Is CVE-2021-37219 being exploited?

There is no known exploitation of CVE-2021-37219 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-41805](https://insights.sbomify.com/CVE-2021-41805/): Privilege escalation in n/a (high 8.8)
- [CVE-2023-2816](https://insights.sbomify.com/CVE-2023-2816/): Consul Envoy Extension Downsteam Proxy Configuration By Upstream Service Owner (high 8.7)
- [CVE-2024-10006](https://insights.sbomify.com/CVE-2024-10006/): Consul L7 Intentions Vulnerable To Headers Bypass (high 8.3)
- [CVE-2024-10005](https://insights.sbomify.com/CVE-2024-10005/): Consul L7 Intentions Vulnerable To URL Path Bypass (high 8.1)
- [CVE-2019-8336](https://insights.sbomify.com/CVE-2019-8336/): HashiCorp Consul Access Restriction Bypass (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-37219 and fix it if it is affected.

What it is: CVE-2021-37219 is a high-severity vulnerability in n/a, published on 7 Sep 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-2021-37219 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/hashicorp/consul (Go): affected all versions; fixed in 1.8.15, 1.9.9, 1.10.2
- github.com/hashicorp/consul (Go): affected all versions; fixed in 1.8.15
- github.com/hashicorp/consul (Go): affected all versions; fixed in 1.8.15
- github.com/hashicorp/consul (Go): affected from 1.10.1; fixed in 1.10.2
- github.com/hashicorp/consul (Go): affected from 1.10.1; fixed in 1.10.2
- github.com/hashicorp/consul (Go): affected from 1.9.0; fixed in 1.9.9
- github.com/hashicorp/consul (Go): affected from 1.9.0; fixed in 1.9.9
- consul (Bitnami): affected all versions; fixed in 1.8.15, 1.9.9, 1.10.2

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-2021-37219/ (Markdown: https://insights.sbomify.com/CVE-2021-37219/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-37219
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-37219
- OSV: https://osv.dev/vulnerability/CVE-2021-37219

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-37219/
Summaries are generated and may contain mistakes; the official description above is the record.