# CVE-2026-10303: ServerCo getssl ACME shell script path injection

> Attackers can exploit path traversal in getssl to write files and execute remote commands via malicious ACME challenge tokens.

- **Severity:** High 7.4 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 16 Jun 2026
- **Updated:** 17 Jun 2026
- **Also known as:** GHSA-9v83-jvh5-6gh3

## What is CVE-2026-10303?

CVE-2026-10303 is a high-severity path traversal vulnerability in ServerCo getssl, published on 16 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In ServerCo getssl version 2.49 and prior, the ACME challenge token returned to the client was not strictly validated against RFC 8555 before being used in challenge-file handling, allowing a maliciously crafted token to influence local path/filename usage during validation. An attacker who can supply ACME challenge responses to getssl (for example, a malicious or compromised CA endpoint, or an on-path adversary able to tamper with that response path) could exploit this to achieve unauthorized file write/path traversal effects, usually with elevated privileges, ultimately allowing for remote command injection. This issue appears related in spirit to CVE-2023-38198, and is an instance of CWE-73, "External control of file name or path." Other ACME shell script handlers may be affected by similar issues.

Weakness: CWE-73 (External Control of File Name or Path)

## Which versions are affected by CVE-2026-10303?


## How do I fix CVE-2026-10303?

No fix has been published for CVE-2026-10303 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-10303 being exploited?

There is no known exploitation of CVE-2026-10303 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10303 and fix it if it is affected.

What it is: CVE-2026-10303 is a high-severity path traversal vulnerability in ServerCo getssl, published on 16 Jun 2026. 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-2026-10303 in the wild and no public exploit code.

Affected product: ServerCo getssl. 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-2026-10303/ (Markdown: https://insights.sbomify.com/CVE-2026-10303/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10303
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10303
- OSV: https://osv.dev/vulnerability/CVE-2026-10303

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10303/
Summaries are generated and may contain mistakes; the official description above is the record.