Skip to main content
CVE-2026-33537VulnerabilityPublished

CVE-2026-33537: LycheeOrg Lychee · Server-Side Request Forgery (SSRF)

Affects LycheeOrg LycheeSource CVE Database V5

0

Not known to be exploited · CVSS 5.3 Medium : upgrade to 7.5.1 when convenient.

Data as of 26 Oct 2026, 07:57 UTC

CVSS 4.0 base score
5.3Medium
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.2% chance of exploitation in 30 days – higher than 19% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in 7.5.1
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 26 Mar 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

What to do

Upgrade Lychee and lycheeorg/Lychee to 7.5.1.

Affected software

ProductAffectedFixed in
LycheeOrgLycheeAffected
  • <7.5.1
Fixed in
  • 7.5.1
GitHublycheeorg/Lycheepkg:github/lycheeorg/LycheeOther threatsAffected
  • <7.5.1
Fixed in
  • 7.5.1

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

The primary mitigation is to upgrade Lychee to version 7.5.1 or later, which contains the fixed IP validation logic that blocks loopback and link-local addresses effectively. Until upgrading, organizations should restrict access to Lychee to trusted users only and limit network access from the Lychee server to internal services, implementing strict egress filtering and network segmentation to prevent SSRF exploitation. Additionally, administrators should review and harden internal services to require strong authentication and authorization, minimizing the impact if SSRF is exploited. Monitoring logs for unusual internal requests originating from Lychee can help detect exploitation attempts. Implementing Web Application Firewalls (WAFs) with SSRF detection rules may provide additional protection. Finally, educating users about the risks of uploading or linking to untrusted URLs can reduce attack vectors.

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.

References

Community reviews

Loading reviews…