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.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
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.
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.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-53536 being exploited?
There is no known exploitation of CVE-2026-53536 in the wild and no public exploit code.
Sources
Also known as GHSA-9723-fmff-mc24.