{"cve":"CVE-2020-26137","nvd":{"published":"2020-09-30T18:15:26.773","modified":"2026-06-17T03:07:39.533","status":"Modified","description":"urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","score":6.5},"cwes":["CWE-74"],"references":["https://bugs.python.org/issue39603","https://github.com/urllib3/urllib3/commit/1dd69c5c5982fae7c87a620d487c2ebf7a6b436b","https://github.com/urllib3/urllib3/pull/1800","https://lists.debian.org/debian-lts-announce/2021/06/msg00015.html","https://lists.debian.org/debian-lts-announce/2023/10/msg00012.html"],"products":["canonical:ubuntu_linux","debian:debian_linux","oracle:communications_cloud_native_core_network_function_cloud_native_environment","oracle:zfs_storage_appliance_kit","python:urllib3"],"source":"nvd","synced_at":"2026-10-19T21:09:53.489947993+00:00"},"epss":{"cve":"CVE-2020-26137","score":0.02269,"percentile":0.83049,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-wqvq-5m8c-6g24","url":"https://osv.dev/vulnerability/GHSA-wqvq-5m8c-6g24","summary":"CRLF injection in urllib3","modified":"2024-11-18T22:47:07.792720Z","packages":[{"ecosystem":"PyPI","name":"urllib3","purl":"pkg:pypi/urllib3","ranges":["<1.25.9"],"fixed":["1.25.9"]}]},{"id":"PYSEC-2020-148","url":"https://osv.dev/vulnerability/PYSEC-2020-148","summary":"","modified":"2023-11-08T04:03:14.251187Z","packages":[{"ecosystem":"PyPI","name":"urllib3","purl":"pkg:pypi/urllib3","ranges":["<1.25.9"],"fixed":["1.25.9"]}]}],"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."]}