{"cve":"CVE-2020-28493","nvd":{"published":"2021-02-01T20:15:12.517","modified":"2026-06-17T03:10:32.070","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":5.3},"cwes":["CWE-400"],"references":["https://github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20","https://github.com/pallets/jinja/pull/1343","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVAKCOO7VBVUBM3Q6CBBTPBFNP5NDXF4/","https://security.gentoo.org/glsa/202107-19","https://snyk.io/vuln/SNYK-PYTHON-JINJA2-1012994"],"products":["fedoraproject:fedora","palletsprojects:jinja"],"source":"nvd","synced_at":"2026-10-19T21:14:10.479542811+00:00"},"epss":{"cve":"CVE-2020-28493","score":0.03589,"percentile":0.89428,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-g3rq-g295-4j3m","url":"https://osv.dev/vulnerability/GHSA-g3rq-g295-4j3m","summary":"Regular Expression Denial of Service (ReDoS) in Jinja2","modified":"2025-02-14T05:26:14.565160Z","packages":[{"ecosystem":"PyPI","name":"jinja2","purl":"pkg:pypi/jinja2","ranges":["<2.11.3"],"fixed":["2.11.3"]}]},{"id":"PYSEC-2021-66","url":"https://osv.dev/vulnerability/PYSEC-2021-66","summary":"","modified":"2023-11-08T04:03:28.543308Z","packages":[{"ecosystem":"PyPI","name":"jinja2","purl":"pkg:pypi/jinja2","ranges":["<2.11.3"],"fixed":["2.11.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}