CVE-2022-24880 – flask-session-captcha

Package

Manager: pip
Name: flask-session-captcha
Vulnerable Version: >=0 <1.2.1

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00238 pctl0.46756

Details

Potential Captcha Validate Bypass in flask-session-captcha ### Impact flask-session-captcha is a package which allows users to extend Flask by adding an image based captcha stored in a server side session. The `captcha.validate()` function would return `None` if passed no value (e.g. by submitting a request with an empty form). If implementing users were checking the return value to be **False**, the captcha verification check could be bypassed. Sample vulnerable code: ```python if captcha.validate() == False: ... # abort else: ... # do stuff ``` ### Patches A new version (1.2.1) is available that fixes the issue. ### Workarounds Users can workaround the issue by not explicitly checking that the value is False. Checking the return value less explicitly should still work. ```python if not captcha.validate(): ... # abort else: ... # do stuff ``` ```python if captcha.validate(): ... # do stuff else: ... # abort ``` ### References https://github.com/Tethik/flask-session-captcha/pull/27 ### For more information If you have any questions or comments about this advisory: * Open an issue in [the github repo](https://github.com/Tethik/flask-session-captcha)

Metadata

Created: 2022-04-26T21:19:52Z
Modified: 2024-09-20T21:03:06Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/04/GHSA-7r87-cj48-wj45/GHSA-7r87-cj48-wj45.json
CWE IDs: ["CWE-253", "CWE-394", "CWE-754"]
Alternative ID: GHSA-7r87-cj48-wj45
Finding: F184
Auto approve: 1