Description
Lychee is a free, open-source photo-management tool. Prior to 7.6.0, the POST /api/v2/Photo::fromUrl flow validates a hostname and its resolved addresses in app/Rules/PhotoUrlRule.php but later passes the original hostname through app/Actions/Import/FromUrl.php to app/Image/Files/DownloadedFile.php for a separate fopen connection. An authenticated attacker who controls DNS responses can cause validation to observe a public address and the subsequent fetch to resolve the same hostname to a private or otherwise forbidden address. This DNS rebinding time-of-check to time-of-use mismatch bypasses the intended server-side request forgery protections and can reach services available from the Lychee server, subject to deployment and TLS behavior. This issue is fixed in version 7.6.0.
References5
Metrics
- CVSS 4.0
-
2.3
LOW
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:L/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 - EPSS — exploit probability
- 0% percentile: 15 · as of 10 November 2026
- CWE
- CWE-367CWE-918
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