CVE-2026-91991

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{"bugzilla": {"description": "tornado: Tornado: Cookie attribute injection via capitalized keyword arguments", "id": "2533964", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2533964"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N", "status": "draft"}, "cwe": "CWE-915", "details": ["A flaw was found in Tornado. An attacker can bypass security validation in the `set_cookie` function by using capitalized or legacy keyword arguments. This allows the attacker to inject arbitrary cookie attributes, such as `Domain` or `SameSite`, and modify cookie security settings. The consequence is the potential to manipulate cookie behavior, which could lead to unintended security impacts."], "name": "CVE-2026-91991", "public_date": "2026-09-15T15:18:32Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-91991\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-91991\nhttps://github.com/tornadoweb/tornado/security/advisories/GHSA-wwv5-g3v4-889x\nhttps://www.vulncheck.com/advisories/tornado-before-6.5.8-cookie-attribute-injection-via-capitalized-kwargs"], "threat_severity": "Moderate"}

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