CVE-2026-0865 — Injection in Software Foundation Cpython

CWE-74 — Injection12 documents8 sources
Severity
5.9MEDIUMNVD
OSV5.7
EPSS
0.1%
top 67.27%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
1
Python Software Foundation Cpython
Timeline
PublishedJan 20
Latest updateMar 19

Description

User-controlled header names and values containing newlines can allow injecting HTTP headers.

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

Affected Packages1 packages

▶CVEListV5python_software_foundation/cpython3.11.0 — 3.11.15+5

🔴Vulnerability Details

5
OSV
python2.7 vulnerabilities↗2026-03-19
▶
OSV
python3.4, python3.5, python3.6, python3.7, python3.8, python3.9, python3.10, python3.11, python3.12, python3.13, python3.14 regression↗2026-03-09
▶
GHSA
GHSA-5mc7-p6pj-r3f5: User-controlled header names and values containing newlines can allow injecting HTTP headers↗2026-01-21
▶
OSV
CVE-2026-0865: User-controlled header names and values containing newlines can allow injecting HTTP headers↗2026-01-20
▶
CVEList
wsgiref.headers.Headers allows header newline injection↗2026-01-20
▶

📋Vendor Advisories

5
Ubuntu
Python 2.7 vulnerabilities↗2026-03-19
▶
Ubuntu
Python regression↗2026-03-09
▶
Ubuntu
Python vulnerabilities↗2026-02-05
▶
Red Hat
cpython: wsgiref.headers.Headers allows header newline injection in Python↗2026-01-20
▶
Debian
CVE-2026-0865: jython - User-controlled header names and values containing newlines can allow injecting ...↗2026
▶

🕵️Threat Intelligence

1
Wiz
CVE-2026-0865 Impact, Exploitability, and Mitigation Steps | Wiz↗
▶
CVE-2026-0865 — Injection | cvebase