MEDIUM

CVE-2019-12387

CVSS v3

6.1

MEDIUM

EPSS Score

2.5 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

twistedPyPIall versions · fixed in 19.2.1

Vendor advisories

CVE-2019-12387 Red Hat Product Security1,226 products fixed · 8 known affected
python-twisted: Improper neutralization of CRLF characters in URIs and HTTP methods
calamari-server as a component of Red Hat Ceph Storage 2 · calamari-server.src as a component of Red Hat Ceph Storage 2 · python-twisted-web as a component of Red Hat Enterprise Linux 6
RHSA-2020:1091 Red Hat Product Security11 products fixed
Red Hat Security Advisory: python-twisted-web security update
RHSA-2019:3172 Red Hat Product Security1,215 products fixed
Red Hat Security Advisory: Red Hat Satellite 6 security, bug fix, and enhancement update

Full record on NVD

Description

In Twisted before 19.2.1, twisted.web did not validate or sanitize URIs or HTTP methods, allowing an attacker to inject invalid characters such as CRLF.

Technical details

Published: 2019-06-10

Frequently asked questions

What is CVE-2019-12387?

In Twisted before 19.2.1, twisted.web did not validate or sanitize URIs or HTTP methods, allowing an attacker to inject invalid characters such as CRLF.

Is CVE-2019-12387 actively exploited?

Active exploitation of CVE-2019-12387 has not been confirmed. Its EPSS score was 2.5% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2019-12387?

CVE-2019-12387 has a CVSS v3 base score of 6.1 (MEDIUM severity).

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