CVE-2026-91991: medium-severity vulnerability in tornadoweb tornado
Tornado before 6.5.8 Cookie Attribute Injection via Capitalized kwargs
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.2%
Tornado before 6.5.8 contains an incomplete fix for cookie attribute injection that allows attackers to inject arbitrary cookie attributes by passing capitalized or legacy keyword arguments to set_cookie. Attackers can embed semicolon-delimited data in capitalized parameters like Domain, Path, or SameSite to bypass validation and modify cookie security attributes.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
Affected products
tornadoweb · tornadoRelated CVEs — tornadoweb tornado
In the same product, most dangerous first.
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