# CVE-2020-36561: Path traversal in github.com/yi-ge/unzip

> Attackers can write or overwrite files outside the target directory via crafted archives, affecting applications using this Go library.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:** Yes
- **Published:** 27 Dec 2022
- **Updated:** 11 Apr 2025
- **Also known as:** GHSA-f5c5-hmw9-v8hx, GO-2020-0035

## What is CVE-2020-36561?

CVE-2020-36561 is a critical path traversal vulnerability in github.com/yi-ge/unzip, published on 27 Dec 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Due to improper path sanitization, archives containing relative file paths can cause files to be written (or overwritten) outside of the target directory.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2020-36561?

3 open source packages ship an affected version, including github.com/yi-ge/unzip. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/yi-ge/unzip` | Go | All versions | 1.0.3-0.20200308084313-2adbaa4891b9 |
| `github.com/yi-ge/unzip` | Go | All versions | 1.0.3-0.20200308084313-2adbaa4891b9 |
| `github.com/yi-ge/unzip` | Go | All versions | 1.0.3-0.20200308084313-2adbaa4891b9 |

Products: Unzip Project Unzip.

## How do I fix CVE-2020-36561?

Upgrade github.com/yi-ge/unzip to 1.0.3-0.20200308084313-2adbaa4891b9 or later.

## Is CVE-2020-36561 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-36561 exists.

## Other vulnerabilities in github.com/yi-ge/unzip

- [CVE-2018-1000035](https://insights.sbomify.com/CVE-2018-1000035/): Memory corruption in n/a (high 7.8)
- [CVE-2018-18384](https://insights.sbomify.com/CVE-2018-18384/): Memory corruption in n/a (medium 5.5)
- [CVE-2014-9913](https://insights.sbomify.com/CVE-2014-9913/): Memory corruption in n/a (medium 4.0)
- [CVE-2016-9844](https://insights.sbomify.com/CVE-2016-9844/): Memory corruption in n/a (medium 4.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-36561 and fix it if it is affected.

What it is: CVE-2020-36561 is a critical path traversal vulnerability in github.com/yi-ge/unzip, published on 27 Dec 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-36561 exists.

Affected packages and fixed versions:
- github.com/yi-ge/unzip (Go): affected all versions; fixed in 1.0.3-0.20200308084313-2adbaa4891b9
- github.com/yi-ge/unzip (Go): affected all versions; fixed in 1.0.3-0.20200308084313-2adbaa4891b9
- github.com/yi-ge/unzip (Go): affected all versions; fixed in 1.0.3-0.20200308084313-2adbaa4891b9

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-2020-36561/ (Markdown: https://insights.sbomify.com/CVE-2020-36561/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-36561
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-36561
- OSV: https://osv.dev/vulnerability/CVE-2020-36561

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-36561/
Summaries are generated and may contain mistakes; the official description above is the record.