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NOTICE UPDATE

NIST has updated the NVD program announcement page with additional information regarding recent concerns and the temporary delays in enrichment efforts.

CVE-2023-30861 Detail

Description

Flask is a lightweight WSGI web application framework. When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches `Set-Cookie` headers, it may send one client's `session` cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met. 1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies. 2. The application sets `session.permanent = True` 3. The application does not access or modify the session at any point during a request. 4. `SESSION_REFRESH_EACH_REQUEST` enabled (the default). 5. The application does not set a `Cache-Control` header to indicate that a page is private or should not be cached. This happens because vulnerable versions of Flask only set the `Vary: Cookie` header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified. This issue has been fixed in versions 2.3.2 and 2.2.5.


Severity



CVSS 3.x Severity and Metrics:

NIST CVSS score matches with CNA score
CNA:  GitHub, Inc.
Base Score:  7.5 HIGH
Vector:  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: The NVD and the CNA have provided the same score. When this occurs only the CNA information is displayed, but the Acceptance Level icon for the CNA is given a checkmark to signify NVD concurrence.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/pallets/flask/commit/70f906c51ce49c485f1d355703e9cc3386b1cc2b Patch 
https://github.com/pallets/flask/commit/afd63b16170b7c047f5758eb910c416511e9c965 Patch 
https://github.com/pallets/flask/releases/tag/2.2.5 Release Notes 
https://github.com/pallets/flask/releases/tag/2.3.2 Release Notes 
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq Vendor Advisory 
https://lists.debian.org/debian-lts-announce/2023/08/msg00024.html
https://security.netapp.com/advisory/ntap-20230818-0006/
https://www.debian.org/security/2023/dsa-5442

Weakness Enumeration

CWE-ID CWE Name Source
CWE-539 Use of Persistent Cookies Containing Sensitive Information Provider acceptance level GitHub, Inc.  

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2023-30861
NVD Published Date:
05/02/2023
NVD Last Modified:
08/20/2023
Source:
GitHub, Inc.