Disclosure summary
An issue was discovered in urllib2 in Python 2.x through 2.7.16 and urllib in Python 3.x through 3.7.3. CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the path component of a URL that lacks a ? character) followed by an HTTP header or a Redis command. This is similar to the CVE-2019-9740 query string issue. This is fixed in: v2.7.17, v2.7.17rc1, v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.9, v3.6.9rc1; v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.
Source-reported weakness categories
CWE-93
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
NIST National Vulnerability Database · NVD-CVE-2019-9947
Open original source · Updated Oct 07, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
| Vendor | Product / association | Version / bounds |
|---|---|---|
| python | python | * {"versionStartIncluding":"3.7.0","versionEndExcluding":"3.7.4"} |
Original records & references
- NIST NVD record
- CVE Program record
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- bugs.python.org — Exploit, Issue Tracking, Patch, Vendor Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Third Party Advisory
- lists.fedoraproject.org
- lists.fedoraproject.org
- security.gentoo.org — Third Party Advisory
- security.netapp.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- access.redhat.com — Third Party Advisory
- bugs.python.org — Exploit, Issue Tracking, Patch, Vendor Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Mailing List, Third Party Advisory
- lists.debian.org — Third Party Advisory
- lists.fedoraproject.org
- lists.fedoraproject.org
- security.gentoo.org — Third Party Advisory
- security.netapp.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
- usn.ubuntu.com — Third Party Advisory
PUBLISHED 2019-03-23T14:29:02-04:00
MODIFIED 2026-10-07T15:17:15-04:00
INGESTED 2026-10-08T12:30:34-04:00