CVE-2019-11324

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-04-18 · updated 2026-06-17
Weakness: CWE-295

Description

The urllib3 library before 1.24.2 for Python mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates, which results in SSL connections succeeding in situations where a verification failure is the correct outcome. This is related to use of the ssl_context, ca_certs, or ca_certs_dir argument.

Affected products

Canonical Ubuntu Linux: 16.04, 18.04, 18.10, 19.04
urllib3: before 1.24.2 — fixed in 1.24.2

How to fix

Upgrade to a fixed version: urllib3 1.24.2. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00039.html
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00041.html
http://www.openwall.com/lists/oss-security/2019/04/19/1
https://access.redhat.com/errata/RHSA-2019:3335
https://access.redhat.com/errata/RHSA-2019:3590
https://github.com/urllib3/urllib3/compare/a6ec68a...1efadf4
https://lists.debian.org/debian-lts-announce/2021/06/msg00015.html
https://lists.debian.org/debian-lts-announce/2023/10/msg00012.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NKGPJLVLVYCL4L4B4G5TIOTVK4BKPG72/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XOSA2NT4DUQDBEIWE6O7KKD24XND7TE2/
https://usn.ubuntu.com/3990-1/
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00039.html

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