# CVE-2026-105689: Penpot: SSRF guard bypass via IPv6 transition addresses (NAT64/6to4/Teredo) in webhook delivery and media download

> Attackers can bypass SSRF protections in Penpot using IPv6 transition addresses to access internal resources or cloud metadata.

- **Severity:** Medium 6.0 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Oct 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-wxgm-8qjw-x445

## What is CVE-2026-105689?

CVE-2026-105689 is a medium-severity server-side request forgery vulnerability in penpot, published on 5 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Penpot is an open-source design and prototyping platform. Prior to 2.18.0, app.util.ssrf/blocked-address? relies on Java InetAddress predicates that do not classify NAT64, 6to4, or Teredo addresses and applies additional CIDR checks only to IPv4 values. Exploitation requires routing through a NAT64 gateway or an attacker-controlled DNS AAAA record; cloud environments with NAT64 gateways are directly exploitable. A user controlling a media import URL, or an administrator controlling a webhook URL, can then supply an IPv6 transition address that embeds a cloud-metadata, loopback, link-local, or private IPv4 target and bypasses the intended SSRF restrictions. Media import can disclose response bodies, while webhook delivery can expose response status as a network-probing side channel. This issue is fixed in version 2.18.0.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-105689?


## How do I fix CVE-2026-105689?

No fix has been published for CVE-2026-105689 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-105689 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-105689 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-105689 and fix it if it is affected.

What it is: CVE-2026-105689 is a medium-severity server-side request forgery vulnerability in penpot, published on 5 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-105689 exists.

Affected product: penpot. 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-2026-105689/ (Markdown: https://insights.sbomify.com/CVE-2026-105689/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-105689
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-105689
- OSV: https://osv.dev/vulnerability/CVE-2026-105689

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-105689/
Summaries are generated and may contain mistakes; the official description above is the record.