Urllib3
CVE-2019-11236
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization CRLF sequence sanitization
|
| Impact | CVSS score of 6.1 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system. |
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Alert meAnalysisAI
In the urllib3 library through 1.24.1 for Python, CRLF injection is possible if the attacker controls the request parameter. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in pypi
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Technical ContextAI · show details
This vulnerability is classified under CWE-93. In the urllib3 library through 1.24.1 for Python, CRLF injection is possible if the attacker controls the request parameter. Affected products include: Python Urllib3. Version information: through 1.24.1.
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Severity by source
AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
In the urllib3 library through 1.24.1 for Python, CRLF injection is possible if the attacker controls the request parameter.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Code injection occurs when an application accepts user input and passes it directly into a language interpreter or evaluator without proper sanitization.
Affected Products (CPE)NVD
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Unbounded memory allocation in urllib3 (1.10.3 through 2.7.x) lets a malicious or machine-in-the-middle HTTP server exha
Resource-exhaustion denial of service in urllib3 1.24 through 2.5.x allows a malicious or attacker-controlled HTTP serve
A decompression-bomb denial-of-service flaw in the urllib3 Python HTTP client library (versions 1.0 through 2.5.x, fixed
Uncontrolled resource consumption in the Python urllib3 HTTP client library (versions 1.22 through 2.6.2) lets a malicio
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Certificate validation bypass in urllib3 1.26.0 through 2.7.x allows a man-in-the-middle attacker who can impersonate th
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The urllib3 library before 1.24.2 for Python mishandles certain cases where the desired set of CA certificates is differ
NVD
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EPSS
GitHub
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