2.1
LOW CVSS 4.0
CVE-2026-6019
BaseCookie.js_output() does not neutralize embedded characters
Description

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.

INFO

Published Date :

April 22, 2026, 8:16 p.m.

Last Modified :

April 22, 2026, 9:23 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-6019 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 LOW 28c92f92-d60d-412d-b760-e73465c3df22
CVSS 4.0 LOW [email protected]
Solution
Mitigate cross-site scripting by properly encoding cookie values.
  • Ensure cookie values are fully encoded.
  • Implement robust output encoding for JavaScript strings.
  • Neutralize HTML parser-sensitive sequences like </script>.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-6019 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-6019 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-6019 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 22, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-150
    Added Reference https://github.com/python/cpython/commit/76b3923d688c0efc580658476c5f525ec8735104
    Added Reference https://github.com/python/cpython/issues/90309
    Added Reference https://github.com/python/cpython/pull/148848
    Added Reference https://mail.python.org/archives/list/[email protected]/thread/IVNWGV2BBNC3RHQAFS22UP4DY56SAXX3/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.