CVE-2026-33644

Severity CVSS v4.0:

LOW

Type:

CWE-918 Server-Side Request Forgery (SSRF)

Publication date:

26/03/2026

Last modified:

30/03/2026

Description

Lychee is a free, open-source photo-management tool. Prior to version 7.5.2, the SSRF protection in `PhotoUrlRule.php` can be bypassed using DNS rebinding. The IP validation check (line 86-89) only activates when the hostname is an IP address. When a domain name is used, `filter_var($host, FILTER_VALIDATE_IP)` returns `false`, skipping the entire check. Version 7.5.2 patches the issue.

Impact

Vector 4.0

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N CVSS v4.0 Severity and Metrics:

Base Score: 2.30 LOW
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): Present
Privileges Required (PR): Low
User Interaction (UI): None
Confidentiality (VC): Low
Integrity (VI): None
Availability (VA): None
Confidentiality (SC): Low
Integrity (SI): None
Availability (SA): None

Base Score 4.0

2.30

Severity 4.0

LOW

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.30 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): None
Availability (A): None