What’s Vulnerable › Vulnerabilities

CVE-2026-33537: Lychee has SSRF bypass via incomplete IP validation in Photo::fromUrl — loopback and link-local IPs not blocked

• Severity: medium (CVSS 5.0 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-03-26 · updated 2026-06-17
• Weakness: CWE-918

Description

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.

Affected products

• LycheeOrg Lychee: before 7.5.1 — fixed in 7.5.1

How to fix

Upgrade to a fixed version: LycheeOrg Lychee 7.5.1. Check the vendor advisory for mitigations.

References

• https://github.com/LycheeOrg/Lychee/commit/41386677681d18cd04e42a35b50bd88bf53a4a6a
• https://github.com/LycheeOrg/Lychee/security/advisories/GHSA-vq6w-prpf-h287

Get alerted when CVE-2026-33537 or the next vulnerability affects your stack