vulnerability / NVI-00013884 / Revision 1
PraisonAI has an origin validation bypass in MCP HTTP Stream transport that allows browser-mediated unauthenticated tool execution on local MCP server
GitHub lists this reviewed advisory for PraisonAI. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
6.9 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
PraisonAI
source listed< 4.6.58
### Summary PraisonAI's MCP HTTP Stream transport uses an unsafe prefix match when validating the `Origin` header. The default localhost allowlist includes origins such as `http://localhost`, and the validation accepts any origin that starts with an allowed value. As a result, an attacker-controlled origin such as `http://localhost.evil.example` passes the localhost origin check. When the MCP HTTP Stream server is started without an API key, which is the CLI default, this allows a malicious webpage to trigger unauthenticated MCP `tools/call` requests against a locally running PraisonAI MCP server. This is best framed as a browser-mediated localhost attack / DNS-rebinding-style Origin validation bypass. The default server binds to `127.0.0.1`, so this is not a directly internet-facing unauthenticated API in the default configuration. ### Details Relevant source locations: - `src/praisonai/praisonai/mcp_server/cli.py` - `src/praisonai/praisonai/mcp_server/transports/http_stream.py` - `src/praisonai/praisonai/mcp_server/server.py` - `src/praisonai/praisonai/mcp_server/adapters/__init__.py` - `src/praisonai/praisonai/mcp_server/adapters/extended_capabilities.py` - `src/praisonai
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-wj6g-v78p-6fx3 ↗
GitHub Advisory Database · vendor advisory
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Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.