# CVE-2023-43620: Croc sender may place ANSI or CSI escape sequences in filename to attach receiver's terminal device

> Attackers can inject ANSI escape sequences via filenames to manipulate the receiver's terminal display in Croc.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 20 Sep 2023
- **Updated:** 24 Sep 2024
- **Also known as:** CLEANSTART-2024-RB67185, GHSA-364c-vvqx-446c, GO-2023-2068

## What is CVE-2023-43620?

CVE-2023-43620 is a high-severity vulnerability in n/a, published on 20 Sep 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

An issue was discovered in Croc through 9.6.5. A sender may place ANSI or CSI escape sequences in a filename to attack the terminal device of a receiver.

Weakness: CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2023-43620?

6 open source packages ship an affected version, including github.com/schollz/croc/v9, github.com/schollz/croc and github.com/schollz/croc/v6. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/schollz/croc/v9` | Go | All versions | 9.6.16 |
| `github.com/schollz/croc/v9` | Go | All versions | 9.6.16 |
| `github.com/schollz/croc/v9` | Go | All versions | 9.6.16 |
| `github.com/schollz/croc` | Go | All versions | None |
| `github.com/schollz/croc/v6` | Go | All versions | None |
| `github.com/schollz/croc/v8` | Go | All versions | None |

Products: Schollz Croc.

## How do I fix CVE-2023-43620?

Upgrade github.com/schollz/croc/v9 to 9.6.16 or later.

## Is CVE-2023-43620 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-43620 exists.

## Other vulnerabilities in n/a

- [CVE-2023-43619](https://insights.sbomify.com/CVE-2023-43619/): Croc sender may send dangerous new files to receiver (high 7.8)
- [CVE-2023-43616](https://insights.sbomify.com/CVE-2023-43616/): Sender can cause a receiver to overwrite files during ZIP extraction in Croc (medium 5.5)
- [CVE-2023-43617](https://insights.sbomify.com/CVE-2023-43617/): Cros secrets may be disclosed to untrusted relay (medium 5.3)
- [CVE-2023-43618](https://insights.sbomify.com/CVE-2023-43618/): Croc requires senders to provide local IP addresses in cleartext (medium 5.3)
- [CVE-2023-43621](https://insights.sbomify.com/CVE-2023-43621/): Croc may expose secret to local users (medium 4.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-43620 and fix it if it is affected.

What it is: CVE-2023-43620 is a high-severity vulnerability in n/a, published on 20 Sep 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-43620 exists.

Affected packages and fixed versions:
- github.com/schollz/croc/v9 (Go): affected all versions; fixed in 9.6.16
- github.com/schollz/croc/v9 (Go): affected all versions; fixed in 9.6.16
- github.com/schollz/croc/v9 (Go): affected all versions; fixed in 9.6.16
- github.com/schollz/croc (Go): affected all versions; no fix listed
- github.com/schollz/croc/v6 (Go): affected all versions; no fix listed
- github.com/schollz/croc/v8 (Go): affected all versions; no fix listed

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-2023-43620/ (Markdown: https://insights.sbomify.com/CVE-2023-43620/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-43620
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-43620
- OSV: https://osv.dev/vulnerability/CVE-2023-43620

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-43620/
Summaries are generated and may contain mistakes; the official description above is the record.