Lychee is a free, open-source photo-management tool. Prior to 7.6.1, when photos_star_visibility is set to anonymous, POST /api/v2/Photo::highlight can fetch and modify a photo without confirming that the caller can see it. BaseApiRequest::validateResolved() invokes SetPhotosHighlightedRequest::processValidatedValues() before authorization, and PhotoPolicy::canHighlight() returns true for anonymous callers without a canSee check. An unauthenticated attacker who can guess photo identifiers can distinguish existing private photos through differing success and not-found responses and can change their is_highlighted state, including for photos in private or password-protected albums. The issue is limited to installations using the non-default anonymous star-visibility setting. This issue is fixed in version 7.6.1.
https://github.com/LycheeOrg/Lychee/security/advisories/GHSA-qcqq-p4pq-7r77
https://github.com/LycheeOrg/Lychee/releases/tag/v7.6.1
https://github.com/LycheeOrg/Lychee/pull/4449
https://github.com/LycheeOrg/Lychee/commit/fe07567c176bbdcda7b276bb6d664dfcd47a9b00
Published: 2026-10-15
Updated: 2026-10-15
Base Score: 6.4
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N
Severity: Medium
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Severity: Medium
Base Score: 2.3
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Severity: Low
EPSS: 0.0023