Home/CVE/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 i
CVE

CVE-2019-9947

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 i

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.

MEDIUM · CVSS 6.1 EPSS 0.01161
Schedule remediation
  • Public exploit or PoC is available
Sigma rules8 YARA rules0
⬡

Weakness Classification

CWE-93Improper Neutralization of CRLF Sequences ('CRLF Injection')
▤

Affected Products & Versions

4
python>= 2.7.0 and < 2.7.17
python>= 3.5.0 and < 3.5.8
python>= 3.6.0 and < 3.6.9
python>= 3.7.0 and < 3.7.4
⚠

Public Exploits & PoCs

1
pocbugs.python.org · issue35906bugs.python.org
◈

Sigma Hunt Rules

8
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
producthighPython Reverse Shell Execution Via PTY And Socket Modules
producthighInline Python Execution - Spawn Shell Via OS System Library
producthighPython One-Liners with Base64 Decoding - Linux
producthighPython Function Execution Security Warning Disabled In Excel
producthighPython One-Liners with Base64 Decoding
producthighPython Spawning Pretty TTY on Windows
▣

Scoring & Timeline

6.1
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD23 Mar 2019 · 06:29 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
⚑

Vendor Advisories

30
suse-csafopenSUSE-SU-2025:15713-1
suse-csafSUSE-SU-2025:20492-1
suse-csafSUSE-SU-2025:20154-1
suse-csafSUSE-SU-2025:20025-1
suse-csafopenSUSE-SU-2024:14434-1
🔗

References & Sources

20
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00062.htmlMailing ListThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00063.htmlMailing ListThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.htmlMailing ListThird Party Advisory
http://www.openwall.com/lists/oss-security/2021/02/04/2Mailing ListThird Party Advisory
https://access.redhat.com/errata/RHSA-2019:1260Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:2030Third Party Advisory
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