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MEDIUM

CVE-2019-9947

CVSS v3

6.1

MEDIUM

EPSS Score

5.3 %

exploit probability, as of 2026-10-19

CISA KEV

No

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

  • python2-attrsAlmaLinux:8all versions · fixed in 17.4.0-10.module_el8.6.0+2781+fed64c13
  • python2-chardetAlmaLinux:8all versions · fixed in 3.0.4-10.module_el8.6.0+2781+fed64c13
  • python2-coverageAlmaLinux:8all versions · fixed in 4.5.1-4.module_el8.6.0+2781+fed64c13
  • python2-CythonAlmaLinux:8all versions · fixed in 0.28.1-7.module_el8.6.0+2781+fed64c13
  • python2-dnsAlmaLinux:8all versions · fixed in 1.15.0-10.module_el8.6.0+2781+fed64c13
  • python2-docsAlmaLinux:8all versions · fixed in 2.7.16-2.module_el8.6.0+2781+fed64c13and 1 other package
  • python2-docutilsAlmaLinux:8all versions · fixed in 0.14-12.module_el8.6.0+2781+fed64c13
  • python2-funcsigsAlmaLinux:8all versions · fixed in 1.0.2-13.module_el8.6.0+2781+fed64c13

15 more package ranges on OSV.dev

Vendor advisories

  • CVE-2019-9947 Red Hat Product Security854 products fixed · 16 known affected

    python: CRLF injection via the path part of the url passed to urlopen()

    python.src as a component of Red Hat Enterprise Linux 5 · python as a component of Red Hat Enterprise Linux 6 · python-devel as a component of Red Hat Enterprise Linux 6

  • ICSA-23-348-10 CISA5 known affected

    Siemens SIMATIC S7-1500

    SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)

  • SSA-398330 Siemens ProductCERT5 known affected

    SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5

    SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= V3.1.0 < V3.1.5 · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= V3.1.0 < V3.1.5 · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= V3.1.0 < V3.1.5

  • RHSA-2020:1462 Red Hat Product Security76 products fixed

    Red Hat Security Advisory: python security update

  • RHSA-2020:1346 Red Hat Product Security45 products fixed

    Red Hat Security Advisory: python security update

  • RHSA-2020:1268 Red Hat Product Security55 products fixed

    Red Hat Security Advisory: python security update

6 more advisories

Full record on NVD

Description

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.

Technical details

Published
2019-03-23

Frequently asked questions

What is 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 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.

Is CVE-2019-9947 actively exploited?

Active exploitation of CVE-2019-9947 has not been confirmed. Its EPSS score was 5.3% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2019-9947?

CVE-2019-9947 has a CVSS v3 base score of 6.1 (MEDIUM severity).

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