https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Fri, 02 Oct 2026 17:00:19 +0000 https://vulnerability.circl.lu/vuln/cve-2026-27205 <p><strong>Affected:</strong> pallets flask</p> <p>Flask 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&#39;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.</p> <p><strong>Affected:</strong> pallets flask</p> <p>Flask 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&#39;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.</p> https://vulnerability.circl.lu/vuln/cve-2026-27205 https://vulnerability.circl.lu/vuln/ghsa-68rp-wp8r-4726 <p><strong>Affected:</strong> PyPI: flask</p> <p>When the `session` object is accessed, Flask should set the `Vary: Cookie` header. This 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.</p> <p>The severity depends on the application&#39;s use of the session, and the cache&#39;s behavior regarding cookies. The risk depends on all these conditions being met.</p> <p>1. The application must be hosted behind a caching proxy that does not ignore responses with cookies. 2. The application does not set a `Cache-Control` header to indicate that a page is private or should not be cached. 3. The application accesses the session in a way that does not access the values, only the keys, and does not mutate the session.</p> <p><strong>Affected:</strong> PyPI: flask</p> <p>When the `session` object is accessed, Flask should set the `Vary: Cookie` header. This 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.</p> <p>The severity depends on the application&#39;s use of the session, and the cache&#39;s behavior regarding cookies. The risk depends on all these conditions being met.</p> <p>1. The application must be hosted behind a caching proxy that does not ignore responses with cookies. 2. The application does not set a `Cache-Control` header to indicate that a page is private or should not be cached. 3. The application accesses the session in a way that does not access the values, only the keys, and does not mutate the session.</p> https://vulnerability.circl.lu/vuln/ghsa-68rp-wp8r-4726 https://vulnerability.circl.lu/vuln/pysec-2026-2151 <p><strong>Affected:</strong> PyPI: flask</p> <p>Flask 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&#39;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.</p> <p><strong>Affected:</strong> PyPI: flask</p> <p>Flask 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&#39;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.</p> https://vulnerability.circl.lu/vuln/pysec-2026-2151