# CVE-2026-105636: Plane: SSRF via HTTP redirect in webhook delivery (allow_redirects not set)

> An attacker can exploit Server-Side Request Forgery in Plane to access internal resources and cloud metadata by leveraging unvalidated HTTP redirects in webhook deliveries.

- **Severity:** Critical 9.9 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **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:** 7 Oct 2026
- **Also known as:** GHSA-mq87-52pf-hm3h

## What is CVE-2026-105636?

CVE-2026-105636 is a critical server-side request forgery vulnerability in makeplane plane, published on 5 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Plane is an open-source project management tool. Prior to 1.4.0, the webhook delivery task in apps/api/plane/bgtasks/webhook_task.py calls requests.post() without allow_redirects=False and does not validate redirect targets. validate_url() blocks private, loopback, link-local, and reserved addresses in the original webhook URL, but the final URL reached after one or more redirects is not checked. A user who can create a workspace can register a webhook pointing to an attacker-controlled public endpoint that returns a 302 redirect to an internal address. The Plane worker then fetches internal resources, including cloud metadata, and stores the response body in webhook_logs, where the attacker can retrieve it through the workspace webhook-logs API. This issue is fixed in 1.4.0.

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

## Which versions are affected by CVE-2026-105636?


## How do I fix CVE-2026-105636?

No fix has been published for CVE-2026-105636 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-105636 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-105636 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-105636 and fix it if it is affected.

What it is: CVE-2026-105636 is a critical server-side request forgery vulnerability in makeplane plane, 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-2026-105636 exists.

Affected product: makeplane plane. 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-2026-105636/ (Markdown: https://insights.sbomify.com/CVE-2026-105636/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-105636
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-105636
- OSV: https://osv.dev/vulnerability/CVE-2026-105636

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-105636/
Summaries are generated and may contain mistakes; the official description above is the record.