CVE-2026-0672

Header injection in http.cookies.Morsel

Published Jan 20, 2026 CVSS 4.0 · 6 Medium EPSS < 1% KEV · Not listed
Description
When using http.cookies.Morsel, user-controlled cookie values and parameters can allow injecting HTTP headers into messages. Patch rejects all control characters within cookie names, values, and parameters.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4455-1 python3.9 security update
Debian DLA Debian DLA DLA-4583-1 python3.9 security update
Ubuntu USN Ubuntu USN USN-8018-1 Python vulnerabilities
Ubuntu USN Ubuntu USN USN-8018-3 Python 2.7 vulnerabilities
Ubuntu USN Ubuntu USN USN-8509-1 Python vulnerabilities
History
Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N'}

threat_severity

Moderate

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Python
Python cpython
Vendors & Products Python
Python cpython
Type Values Removed Values Added
Description User-controlled cookie values and parameters can allow injecting HTTP headers. Fix rejects all control characters within cookie names, values, and parameters. When using http.cookies.Morsel, user-controlled cookie values and parameters can allow injecting HTTP headers into messages. Patch rejects all control characters within cookie names, values, and parameters.
References
Type Values Removed Values Added
Description User-controlled cookie values and parameters can allow injecting HTTP headers. Fix rejects all control characters within cookie names, values, and parameters.
Title Header injection in http.cookies.Morsel
Weaknesses CWE-93
References
Metrics cvssV4_0

{'score': 6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
PSF
Published
Updated
Mar 3, 2026, 2:43 PM
Reserved
Jan 7, 2026, 5:08 PM
Status
Deferred
Published
Jan 20, 2026, 10:15 PM
Modified
Jun 17, 2026, 10:11 AM
Severity
Moderate
Public date
Jan 20, 2026, 9:52 PM