# CVE-2026-109118: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in rdiffweb

> Authenticated users can bypass path restrictions to read or delete files outside the intended repository via encoded traversal sequences.

- **Severity:** Medium 4.6 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 16 Oct 2026
- **Updated:** 16 Oct 2026
- **Also known as:** GHSA-75v3-2c25-pfq5

## What is CVE-2026-109118?

CVE-2026-109118 is a medium-severity path traversal vulnerability in ikus-soft rdiffweb, published on 16 Oct 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Improper path containment check in ikus060 rdiffweb 7.1.1 allows an authenticated user to cause the browse, restore, history and delete operations to resolve to a path outside the repository being operated on, via a percent-encoded traversal sequence (%2e%2e) in the request path, because the containment check uses a string prefix comparison (startswith) instead of a filesystem path boundary check. The target must be a sibling path whose name begins with the repository path, and the user already hold permissions on it; the issue can mislead a user into operating on, or deleting, data other than the repository displayed

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

## Which versions are affected by CVE-2026-109118?


## How do I fix CVE-2026-109118?

No fix has been published for CVE-2026-109118 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-109118 being exploited?

There is no known exploitation of CVE-2026-109118 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-109118 and fix it if it is affected.

What it is: CVE-2026-109118 is a medium-severity path traversal vulnerability in ikus-soft rdiffweb, published on 16 Oct 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-109118 in the wild and no public exploit code.

Affected product: ikus-soft rdiffweb. 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-2026-109118/ (Markdown: https://insights.sbomify.com/CVE-2026-109118/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-109118
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-109118
- OSV: https://osv.dev/vulnerability/CVE-2026-109118

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-109118/
Summaries are generated and may contain mistakes; the official description above is the record.