typebot.io: Improper Limitation of a Pathname to a Restricted Directory
CVE-2026-48768 is a critical-severity improper limitation of a pathname to a restricted directory vulnerability in typebot.io from baptisteArno, with a CVSS 3.1 base score of 9.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected typebot.io versions: < 3.17.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.33% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of typebot.io you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| baptisteArno | typebot.io | < 3.17.0 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- LowSome restricted data can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N. Scored by CNA (github.com).
Official description
TypeBot is a chatbot builder tool. In versions 3.16.1 and earlier, POST /api/blocks/file-input/v3/generate-upload-url is unauthenticated and uses unsanitized fileName input to construct public/ S3 object keys, while issuing presigned PUT URLs that do not bind Content-Type. As a result, any anonymous visitor to a published bot with a file input can upload attacker-controlled HTML, SVG, or JS to attacker-chosen subpaths, including other tenants’ publicly served result paths, enabling arbitrary content hosting and potential stored XSS on the storage origin. ../ traversal is blocked by S3/MinIO canonicalization (signature mismatch), but forward-slash path injection is exploitable. This issue has been fixed in version 3.17.0.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in typebot.io
- 8.7 High severity
- 9.1 Critical severity
- 9.9 Critical severity
- 8.2 High severity
- 7.6 High severity
- 7.1 High severity
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 8.8 High severity
- 7.7 High severity
- 8.7 High severity
- 8.6 High severity
- 7.1 High severity
- 7.5 High severity
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