CVE-2026-33738

<!-- PoC Concept for CVE-2026-33738 1. Log in to Lychee and upload a photo. 2. Set the 'description' field of the photo to the following payload: --> <img src=x onerror=alert('CVE-2026-33738_XSS')> <!-- Alternatively, using script tags (depending on RSS reader parser): <script>alert('CVE-2026-33738_XSS')</script> 3. Access the public feed endpoint: GET /feed or /feed?type=atom 4. Observe that the JavaScript alert executes when the feed is loaded in a vulnerable RSS reader or browser. -->

{"cve": {"id": "CVE-2026-33738", "sourceIdentifier": "[email protected]", "published": "2026-03-26T21:17:08.110", "lastModified": "2026-03-30T18:45:14.510", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Lychee is a free, open-source photo-management tool. Prior to version 7.5.3, the photo `description` field is stored without HTML sanitization and rendered using `{!! $item->summary !!}` (Blade unescaped output) in the RSS, Atom, and JSON feed templates. The `/feed` endpoint is publicly accessible without authentication, allowing any RSS reader to execute attacker-controlled JavaScript. Version 7.5.3 fixes the issue."}, {"lang": "es", "value": "Lychee es una herramienta de gestión de fotos gratuita y de código abierto. Antes de la versión 7.5.3, el campo `description` de la foto se almacena sin saneamiento HTML y se renderiza usando `{!! $item-&gt;summary !!}` (salida sin escape de Blade) en las plantillas de feeds RSS, Atom y JSON. El endpoint `/feed` es públicamente accesible sin autenticación, permitiendo que cualquier lector RSS ejecute JavaScript controlado por el atacante. La versión 7.5.3 corrige el problema."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:H/SI:L/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": 4.8, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "LOW", "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:R/S:C/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.3, "impactScore": 2.7}]}, "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:lycheeorg:lychee:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.5.3", "matchCriteriaId": "9FC80F07-5E2D-4C7A-8D56-32C4C8CFAA6F"}]}]}], "references": [{"url": "https://github.com/LycheeOrg/Lychee/commit/d2e2606a0223d5a384d5b806db1b31eb587adc5c", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/LycheeOrg/Lychee/pull/4218", "source": "[email protected]", "tags": ["Issue Tracking"]}, {"url": "https://github.com/LycheeOrg/Lychee/releases/tag/v7.5.3", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/LycheeOrg/Lychee/security/advisories/GHSA-5574-7f3r-hm9j", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/LycheeOrg/Lychee/security/advisories/GHSA-5574-7f3r-hm9j", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}