High
mako — security advisory
Mako is a template library written in Python. Prior to 1.3.11, TemplateLookup.get_template() is vulnerable to path traversal when a URI starts with // (e.g., //../../../secret.txt). The root cause is an inconsistency between two slash-stripping implementations. Any file readable by the process can be returned as rendered template content when an application passes untrusted input directly to TemplateLookup.get_template(). This vulnerability is fixed in 1.3.11.
- Products
- mako
- Affected versions
- 1.2.4+ds-1, 1.2.4+ds-2, 1.3.1-1, 1.3.10-1, 1.3.10-2, 1.3.10-3, 1.3.2-1, 1.3.5-1, 1.3.5-1.1, 1.3.6-1, 1.3.8-1, 1.3.8-2, 1.3.9-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-41205
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:38 UTC · Revision 2
Source evidence
Mako is a template library written in Python. Prior to 1.3.11, TemplateLookup.get_template() is vulnerable to path traversal when a URI starts with // (e.g., //../../../secret.txt). The root cause is an inconsistency between two slash-stripping implementations. Any file readable by the process can be returned as rendered template content when an application passes untrusted input directly to TemplateLookup.get_template(). This vulnerability is fixed in 1.3.11.
osv:DEBIAN-CVE-2026-41205
mako
Fixed versions: Not specified
mako
Fixed versions: Not specified
mako
Fixed versions: Not specified
Complete source record
{
"id": "f8d479fd7a4a9b30f79fce21374e1661b6bd29b6233a102e4e2418082b68e1b9",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-41205",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-41205",
"summary": "Mako is a template library written in Python. Prior to 1.3.11, TemplateLookup.get_template() is vulnerable to path traversal when a URI starts with // (e.g., //../../../secret.txt). The root cause is an inconsistency between two slash-stripping implementations. Any file readable by the process can be returned as rendered template content when an application passes untrusted input directly to TemplateLookup.get_template(). This vulnerability is fixed in 1.3.11.",
"evidence": "osv:DEBIAN-CVE-2026-41205",
"products": [
{
"name": {
"value": "mako",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.2.4+ds-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.4+ds-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.10-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.10-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.10-3",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.2-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.5-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.5-1.1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.6-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.8-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.8-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.3.9-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "mako",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.3.10-1",
"evidence": "/affected/1/versions"
},
{
"value": "1.3.10-2",
"evidence": "/affected/1/versions"
},
{
"value": "1.3.10-3",
"evidence": "/affected/1/versions"
},
{
"value": "1.3.9-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "mako",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.3.10-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.3.10-2",
"evidence": "/affected/2/versions"
},
{
"value": "1.3.10-3",
"evidence": "/affected/2/versions"
},
{
"value": "1.3.9-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-41205",
"aliases": [
"DEBIAN-CVE-2026-41205"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mako",
"purl": "pkg:deb/debian/mako?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1.2.4+ds-1",
"1.2.4+ds-2",
"1.3.1-1",
"1.3.10-1",
"1.3.10-2",
"1.3.10-3",
"1.3.2-1",
"1.3.5-1",
"1.3.5-1.1",
"1.3.6-1",
"1.3.8-1",
"1.3.8-2",
"1.3.9-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-41205.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mako",
"purl": "pkg:deb/debian/mako?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1.3.10-1",
"1.3.10-2",
"1.3.10-3",
"1.3.9-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-41205.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mako",
"purl": "pkg:deb/debian/mako?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1.3.10-1",
"1.3.10-2",
"1.3.10-3",
"1.3.9-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-41205.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-27T09:47:31.374720944Z",
"provider": "osv",
"upstream": [
"CVE-2026-41205"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-41205"
]
},
"related_cves": [
{
"value": "CVE-2026-41205",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 460940,
"published_at": "2026-04-23T19:17:29.27+00:00"
}