How severe is CVE-2019-11236?

CVE-2019-11236 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2019-11236 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-11236?

CVE-2019-11236 affects Python Urllib3. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-11236?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-11236 published?

CVE-2019-11236 was published on 2019-04-15 and last updated on 2026-06-17.

CVE-2019-11236

CVE-2019-11236 is a medium-severity vulnerability in Python Urllib3 with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-93.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-93
Affected product: Python Urllib3
Published: 2019-04-15
Last modified: 2026-06-17

Description

In the urllib3 library through 1.24.1 for Python, CRLF injection is possible if the attacker controls the request parameter.

Frequently asked questions

What is CVE-2019-11236?: In the urllib3 library through 1.24.1 for Python, CRLF injection is possible if the attacker controls the request parameter.
How severe is CVE-2019-11236?: CVE-2019-11236 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2019-11236 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-11236?: CVE-2019-11236 affects Python Urllib3. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-11236?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-11236 published?: CVE-2019-11236 was published on 2019-04-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:python:urllib3:*:*:*:*:*:*:*:*

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