Low
Lychee has SSRF bypass via DNS rebinding — PhotoUrlRule only validates IP addresses, not hostnames resolving to internal IPs
Type: advisorySources: OSV
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($host, FILTER_VALIDATE_IP)` returns `false`, skipping the entire check. Version 7.5.2 patches the issue.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-33644
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 14:05 UTC · Revision 1
Source evidence
Lychee has SSRF bypass via DNS rebinding — PhotoUrlRule only validates IP addresses, not hostnames resolving to internal IPs
core-osv · Original sourcePublished 26 Mar 2026, 20:04 UTC
Lychee is a free, open-source photo-management tool. Prior to version 7.5.2, the SSRF protection in `PhotoUrlRule.php` can be bypassed using DNS rebinding. The IP validation check (line 86-89) only activates when the hostname is an IP address. When a domain name is used, `filter_var($host, FILTER_VALIDATE_IP)` returns `false`, skipping the entire check. Version 7.5.2 patches the issue.
osv:CVE-2026-33644
Complete source record
{
"id": "9e5a888e39101356240d447b2dca6877688a5960887b912fc768e92bf7638f88",
"url": "https://osv.dev/vulnerability/CVE-2026-33644",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Lychee has SSRF bypass via DNS rebinding — PhotoUrlRule only validates IP addresses, not hostnames resolving to internal IPs",
"summary": "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.",
"evidence": "osv:CVE-2026-33644",
"products": [],
"severity": "low",
"structured": {
"id": "CVE-2026-33644",
"aliases": [
"CVE-2026-33644",
"GHSA-5245-4p8c-jwff"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "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"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/lycheeorg/lychee",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "28c5261fb9deab4f9420c8cc2f73a87425939107"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "7.5.2"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "28c5261fb9deab4f9420c8cc2f73a87425939107"
}
],
"source": "REFERENCES_COMMIT"
},
{
"cpe": "cpe:2.3:a:lycheeorg:lychee:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "7.5.2"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v7.5.1",
"v7.5.0",
"v7.4.2",
"v7.4.1",
"v7.4.0",
"v7.3.3",
"v7.3.2",
"v7.3.1",
"v7.3.0",
"v7.2.1",
"v7.2.0",
"v7.1.2",
"v7.1.1",
"v7.1.0",
"v7.0.1",
"v7.0.0",
"v6.10.4",
"v6.10.3",
"v6.10.2",
"v6.10.1",
"v6.10.0",
"v6.9.4",
"v6.9.3",
"v6.9.2",
"v6.9.1",
"v6.9.0",
"v6.8.1",
"v6.8.0",
"v6.7.2",
"v6.7.1",
"v6.7.0",
"v6.6.14",
"v6.6.13",
"v6.6.12",
"v6.6.11",
"v6.6.10",
"v6.6.9",
"v6.6.8",
"v6.6.7",
"v6.6.6",
"v6.6.5",
"v6.6.4",
"v6.6.3",
"v6.6.2",
"v6.6.1",
"v6.6.0",
"v6.5.3",
"v6.5.2",
"v6.5.1",
"v6.5.0",
"v6.4.2",
"v6.4.1",
"v6.4.0",
"v6.3.5",
"v6.3.4",
"v6.3.3",
"v6.3.2",
"v6.3.1",
"v6.3.0",
"v6.2.0",
"v6.1.2",
"v6.1.1",
"v6.1.0",
"v6.0.1",
"v6.0.0",
"v5.5.1",
"v5.5.0",
"v5.4.0",
"v5.3.1",
"v5.3.0",
"v5.2.2",
"v5.2.1",
"v5.2.0",
"v5.1.2",
"v5.1.1",
"v5.1.0",
"v5.0.3",
"v5.0.2",
"v5.0.1",
"v5.0.0",
"v5.0.0-beta",
"v4.13.0",
"v4.12.0",
"v4.11.1",
"v4.11.0",
"v4.10.0",
"v4.9.4",
"v4.9.3",
"v4.9.3-RC",
"v4.9.2",
"v4.9.1",
"v4.9.0",
"v4.8.1",
"v4.8.0",
"v4.7.4",
"v4.7.3",
"v4.7.2",
"v4.7.1",
"v4.7.0",
"v4.6.5",
"v4.6.4",
"v4.6.3-RC1",
"v4.6.2",
"v4.6.2-RC2",
"v4.6.2-RC1",
"v4.6.1-RC2",
"v4.6.1",
"v4.6.1-RC1",
"v4.6.0",
"v4.6.0-RC3",
"v4.6.0-RC2",
"v4.6.0-RC",
"v4.5.3",
"v4.5.2",
"v4.5.1",
"v4.5.0",
"v4.4.0",
"v4.3.6",
"v4.3.5",
"v4.3.4",
"v4.3.0",
"v4.2.2",
"v4.2.1",
"v4.2.0",
"v4.1.0",
"v4.0.8",
"v4.0.7",
"v4.0.6",
"v4.0.5",
"v4.0.4",
"v4.0.3",
"v4.0.2",
"v4.0.1",
"v4.0.0",
"v4.0.0-beta.2",
"v4.0.0-beta.1",
"v4.0.0-alpha.1"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33644.json"
}
}
],
"modified": "2026-10-28T02:30:29.326826615Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33644.json",
"https://github.com/LycheeOrg/Lychee/security/advisories/GHSA-5245-4p8c-jwff",
"https://nvd.nist.gov/vuln/detail/CVE-2026-33644",
"https://github.com/LycheeOrg/Lychee/commit/28c5261fb9deab4f9420c8cc2f73a87425939107"
],
"provider_metadata": {
"cwe_ids": [
"CWE-918"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33644.json"
}
},
"related_cves": [
{
"value": "CVE-2026-33644",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 496219,
"published_at": "2026-03-26T20:04:18.728+00:00"
}