#VU122814 CRLF injection in Python - CVE-2026-0672
Published: February 13, 2026
Python
Python.org
Description
The vulnerability allows a remote attacker to inject arbitrary data in server response.
The vulnerability exists due to insufficient validation of attacker-supplied data when using http.cookies.Morsel. A remote attacker can pass specially crafted data to the application containing CR-LF characters and modify application behavior leading to a spoofing attack.
Remediation
External links
- https://github.com/python/cpython/commit/62700107418eb2cca3fc88da036a243ea975f172
- https://github.com/python/cpython/commit/712452e6f1d4b9f7f8c4c92ebfcaac1705faa440
- https://github.com/python/cpython/commit/7852d72b653fea0199acf5fc2a84f6f8b84eba8d
- https://github.com/python/cpython/commit/918387e4912d12ffc166c8f2a38df92b6ec756ca
- https://github.com/python/cpython/commit/95746b3a13a985787ef53b977129041971ed7f70
- https://github.com/python/cpython/commit/b1869ff648bbee0717221d09e6deff46617f3e85
- https://github.com/python/cpython/issues/143919
- https://github.com/python/cpython/pull/143920
- https://mail.python.org/archives/list/security-announce@python.org/thread/6VFLQQEIX673KXKFUZXCUNE5AZOGZ45M/