CVE-2026-6019

http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.

CVSS

No CVSS.

References

Link	Resource
https://github.com/python/cpython/commit/3c59b8b53fc75c7f9578d16fb8201ceb43e8f76c
https://github.com/python/cpython/commit/76b3923d688c0efc580658476c5f525ec8735104
https://github.com/python/cpython/commit/f795e042043dfe26c42e1971d4502c1cdc4c65b8
https://github.com/python/cpython/issues/90309
https://github.com/python/cpython/pull/148848
https://mail.python.org/archives/list/security-announce@python.org/thread/IVNWGV2BBNC3RHQAFS22UP4DY56SAXX3/

Configurations

No configuration.

History

29 Apr 2026, 16:16

Type	Values Removed	Values Added
References		() https://github.com/python/cpython/commit/3c59b8b53fc75c7f9578d16fb8201ceb43e8f76c - () https://github.com/python/cpython/commit/f795e042043dfe26c42e1971d4502c1cdc4c65b8 -

22 Apr 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-22 20:16

Updated : 2026-04-29 16:16

NVD link : CVE-2026-6019

Mitre link : CVE-2026-6019

CVE.ORG link : CVE-2026-6019

JSON object : View

Products Affected

No product.

CWE

CWE-150

Improper Neutralization of Escape, Meta, or Control Sequences

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