jinja2 — security advisory
This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory.
- Products
- jinja2
- Affected versions
- Not specified
- Fixed versions
- 2.11.3-1
- CVEs
- CVE-2020-28493
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 13:50 UTC · Revision 1
Source evidence
This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory.
osv:DEBIAN-CVE-2020-28493
jinja2
Fixed versions: 2.11.3-1
jinja2
Fixed versions: 2.11.3-1
jinja2
Fixed versions: 2.11.3-1
Complete source record
{
"id": "dc21a7c828258acabdfca894a426fb23de9514978f5bb8a107e0084ba1bdbd1b",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-28493",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2020-28493",
"summary": "This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory.",
"evidence": "osv:DEBIAN-CVE-2020-28493",
"products": [
{
"name": {
"value": "jinja2",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.11.3-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "jinja2",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.11.3-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "jinja2",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.11.3-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2020-28493",
"aliases": [
"DEBIAN-CVE-2020-28493"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.11.3-1"
}
]
}
],
"package": {
"name": "jinja2",
"purl": "pkg:deb/debian/jinja2?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-28493.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.11.3-1"
}
]
}
],
"package": {
"name": "jinja2",
"purl": "pkg:deb/debian/jinja2?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-28493.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.11.3-1"
}
]
}
],
"package": {
"name": "jinja2",
"purl": "pkg:deb/debian/jinja2?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-28493.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T12:02:43.317363824Z",
"provider": "osv",
"upstream": [
"CVE-2020-28493"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-28493"
]
},
"related_cves": [
{
"value": "CVE-2020-28493",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 452884,
"published_at": "2021-02-01T20:15:12.517+00:00"
}