# CVE-2026-39374: Plane IDOR: Cross-Project Issue Date Modification via Bulk Update Endpoint

> A project member can modify issue dates across any workspace or project due to missing authorization checks in the bulk update endpoint.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A: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:** 7 Apr 2026
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-4q54-h4x9-m329

## What is CVE-2026-39374?

CVE-2026-39374 is a medium-severity missing authorization vulnerability in makeplane plane, published on 7 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Plane is an an open-source project management tool. Prior to 1.3.0, the IssueBulkUpdateDateEndpoint allows a project member (ADMIN or MEMBER) to modify the start_date and target_date of ANY issue across the entire Plane instance, regardless of workspace or project membership. The endpoint fetches issues by ID without filtering by workspace or project, enabling cross-boundary data modification. This vulnerability is fixed in 1.3.0.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-39374?

It affects 1 product.


Products: Plane Plane.

## How do I fix CVE-2026-39374?

No fix has been published for CVE-2026-39374 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-39374 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-39374 exists.

## Other vulnerabilities in makeplane plane

- [CVE-2024-47830](https://insights.sbomify.com/CVE-2024-47830/): Plane allows server side request forgery via /_next/image endpoint (critical 9.3)
- [CVE-2026-30242](https://insights.sbomify.com/CVE-2026-30242/): Plane: SSRF via Incomplete IP Validation in Webhook URL Serializer (high 8.5)
- [CVE-2026-46558](https://insights.sbomify.com/CVE-2026-46558/): Missing authorization in plane (high 8.3)
- [CVE-2026-39843](https://insights.sbomify.com/CVE-2026-39843/): Plane has a Server-Side Request Forgery (SSRF) in Favicon Fetching (high 7.7)
- [CVE-2026-27706](https://insights.sbomify.com/CVE-2026-27706/): Plane Vulnerable to Full Read SSRF via Favicon Fetching in "Add Link" Feature (high 7.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-39374 and fix it if it is affected.

What it is: CVE-2026-39374 is a medium-severity missing authorization vulnerability in makeplane plane, published on 7 Apr 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-2026-39374 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-2026-39374/ (Markdown: https://insights.sbomify.com/CVE-2026-39374/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-39374
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-39374
- OSV: https://osv.dev/vulnerability/CVE-2026-39374

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-39374/
Summaries are generated and may contain mistakes; the official description above is the record.