# CVE-2026-53536: Activepieces: Cross-tenant file download via missing JWT audience check on step-files signed URL

> Authenticated users can download step-files from other tenants due to missing JWT audience validation and null checks.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/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:** 16 Jul 2026
- **Updated:** 18 Jul 2026
- **Also known as:** GHSA-9723-fmff-mc24

## What is CVE-2026-53536?

CVE-2026-53536 is a medium-severity missing authorization vulnerability in activepieces, published on 16 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Activepieces is an open source AI workflow automation platform. Prior to 0.83.0, the /v1/step-files/signed download endpoint verified the supplied JWT against the shared signing secret but did not check the token's audience, and combined with a missing null-check on the decoded fileId, this allowed any caller holding any valid Activepieces JWT (including a freshly created user's own access token) to receive a step-file belonging to another tenant. The file returned was whatever PostgreSQL happened to scan first for type = FLOW_STEP_FILE, varying over time as the database changed, so an authenticated user could obtain step-file attachments belonging to other tenants on the same instance; the attacker could not target a specific victim or file, and the access was read-only with no integrity or availability impact. This issue is fixed in version 0.83.0.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key), CWE-345 (Insufficient Verification of Data Authenticity)

## Which versions are affected by CVE-2026-53536?


## How do I fix CVE-2026-53536?

No fix has been published for CVE-2026-53536 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-53536 being exploited?

There is no known exploitation of CVE-2026-53536 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53536 and fix it if it is affected.

What it is: CVE-2026-53536 is a medium-severity missing authorization vulnerability in activepieces, published on 16 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53536 in the wild and no public exploit code.

Affected product: activepieces. 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-2026-53536/ (Markdown: https://insights.sbomify.com/CVE-2026-53536/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53536
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53536
- OSV: https://osv.dev/vulnerability/CVE-2026-53536

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53536/
Summaries are generated and may contain mistakes; the official description above is the record.