CVSS VectorNVD
CVSS:4.0/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
Lifecycle Timeline
2DescriptionNVD
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.
AnalysisAI
CPython's http.cookies.Morsel.js_output() method generates inline script snippets that fail to neutralize the HTML parser-sensitive sequence </script>, allowing attackers with high privilege levels to inject arbitrary JavaScript by crafting malicious cookie values. While the method escapes double quotes for JavaScript string context, it does not prevent premature termination of the script element through </script> injection, resulting in limited information disclosure. …
Sign in for full analysis, threat intelligence, and remediation guidance.
Share
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-25079