# CVE-2021-36767: Weak cryptography in n/a

> An attacker can obtain a weakly-hashed server password via unauthenticated requests and crack it offline to gain unauthorized access to the Digi RealPort server.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 8 Oct 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-22vf-qc4p-vc3x

## What is CVE-2021-36767?

CVE-2021-36767 is a critical vulnerability in n/a, published on 8 Oct 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Digi RealPort through 4.10.490, authentication relies on a challenge-response mechanism that gives access to the server password, making the protection ineffective. An attacker may send an unauthenticated request to the server. The server will reply with a weakly-hashed version of the server's access password. The attacker may then crack this hash offline in order to successfully login to the server.

Weakness: CWE-916 (Use of Password Hash With Insufficient Computational Effort)

## Which versions are affected by CVE-2021-36767?

It affects 19 products.


Products: Digi 6350-Sr Firmware, Digi Cm Firmware, Digi Connect Es Firmware, Digi Connectport Lts 8\/16\/32 Firmware, Digi Connectport Ts 8\/16 Firmware, Digi One Ia Firmware, Digi One Iap Firmware, Digi One Iap Haz Firmware, Digi Passport Integrated Console Server Firmware, Digi Portserver Ts Firmware, Digi Portserver Ts M Mei Firmware, Digi Portserver Ts Mei Firmware, Digi Portserver Ts Mei Hardened Firmware, Digi Portserver Ts P Mei Firmware, Digi Realport, Digi Transport Wr11 Xt Firmware, Digi Wr21 Firmware, Digi Wr31 Firmware, Digi Wr44 R Firmware.

## How do I fix CVE-2021-36767?

No fix has been published for CVE-2021-36767 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-36767 being exploited?

There is no known exploitation of CVE-2021-36767 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-35977](https://insights.sbomify.com/CVE-2021-35977/): Memory corruption in n/a (critical 9.8)
- [CVE-2021-35979](https://insights.sbomify.com/CVE-2021-35979/): Auth bypass in n/a (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-36767 and fix it if it is affected.

What it is: CVE-2021-36767 is a critical vulnerability in n/a, published on 8 Oct 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-2021-36767 in the wild and no public exploit code.

Affected product: n/a. 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-2021-36767/ (Markdown: https://insights.sbomify.com/CVE-2021-36767/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-36767
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-36767
- OSV: https://osv.dev/vulnerability/CVE-2021-36767

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-36767/
Summaries are generated and may contain mistakes; the official description above is the record.