CVE-2026-27205 Detail
Received
This CVE record has recently been published to the CVE List and has been included within the NVD dataset. DescriptionFlask is a web server gateway interface (WSGI) web application framework. In versions 3.1.2 and below, when the session object is accessed, Flask should set the Vary: Cookie header., resulting in a Use of Cache Containing Sensitive Information vulnerability. The logic instructs caches not to cache the response, as it may contain information specific to a logged in user. This is handled in most cases, but some forms of access such as the Python in operator were overlooked. The severity and risk depend on the application being hosted behind a caching proxy that doesn't ignore responses with cookies, not setting a Cache-Control header to mark pages as private or non-cacheable, and accessing the session in a way that only touches keys without reading values or mutating the session. The issue has been fixed in version 3.1.3. Metrics
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Weakness Enumeration
Quick InfoCVE Dictionary Entry:CVE-2026-27205 NVD Published Date: 02/21/2026 NVD Last Modified: 02/21/2026 Source: GitHub, Inc. |
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