CVE-2026-48763: TypeBot has Arbitrary S3 Object Write in deprecated public upload endpoint via attacker-controlled filePath
TypeBot is a chatbot builder tool. Versions prior to 3.17.0 expose a deprecated public upload endpoint at GET /api/v1/typebots/{typebotId}/blocks/{blockId}/storage/upload-url that accepts an attacker-controlled filePath and returns a presigned S3 PUT URL for that exact key. Because the endpoint only checks that the referenced typebot is public and that the referenced block is a file input block, an unauthenticated attacker who knows a valid public typebotId and blockId can request presigned upload URLs for arbitrary objects in the shared bucket, including private/... and other tenants' public/... paths. Version 3.17.0 fixes this issue.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
TypeBotto a version that resolves this vulnerability.Fixed in 3.17.0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-48763?
The severity of CVE-2026-48763 is high, with a CVSS score of 8.2.
How does CVE-2026-48763 affect TypeBot?
CVE-2026-48763 allows an attacker to exploit a deprecated public upload endpoint to write arbitrary objects to S3.
What versions of TypeBot are affected by CVE-2026-48763?
All versions of TypeBot prior to 3.17.0 are affected by CVE-2026-48763.
How can I mitigate CVE-2026-48763?
To mitigate CVE-2026-48763, upgrade to TypeBot version 3.17.0 or later.
What action should I take if I cannot upgrade due to CVE-2026-48763?
If you cannot upgrade, consider implementing strict validation on the filePath parameter and disabling access to the deprecated endpoint.