TI-2022-08690 Aliases CVE-2022-24880 GHSA-7r87-cj48-wj45

Potential Captcha Validate Bypass in flask-session-captcha

LOW 32CWE-253Published 2022-04-25 · Updated 2025-04-23

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: None · Low · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

flask-session-captcha is a package which allows users to extend Flask by adding an image based captcha stored in a server side session. In versions prior to 1.2.1, he `captcha.validate()` function would return `None` if passed no value (e.g. by submitting an having an empty form). If implementing users were checking the return value to be **False**, the captcha verification check could be bypassed. Version 1.2.1 fixes the issue. Users can workaround the issue by not explicitly checking that the value is False. Checking the return value less explicitly should still work.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.01206 68th percentileScored 2026-11-07

Fix Fixed flask-session-captcha (Tethik): 1.2.1flask-session-captcha (PyPI): 1.2.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Tethik	flask-session-captcha	before 1.2.1	1.2.1	Patch available	CNA
—	flask-session-captcha (PyPI)	before 1.2.1	1.2.1	Patch available	GHSA-7r87-cj48-wj45

flask-session-captcha VendorTethik Affected before 1.2.1 Fixed in 1.2.1 Patch available CNA
flask-session-captcha (PyPI) Vendor— Affected before 1.2.1 Fixed in 1.2.1 Patch available GHSA-7r87-cj48-wj45

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:flask-session-captcha_project:flask-session-captcha::::::::	before 1.2.1	Vulnerable	Flask-session-captcha Project

cpe:2.3:a:flask-session-captcha_project:flask-session-captcha:*:*:*:*:*:*:*:* Versions before 1.2.1 Vulnerable ·Flask-session-captcha Project

Remediation

Fix · CNA flask-session-captcha (Tethik) Fixed in 1.2.1
Fix · GHSA-7r87-cj48-wj45 flask-session-captcha (PyPI) Fixed in 1.2.1 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2022-24880
2026-10-03 Alias added: GHSA-7r87-cj48-wj45

References

Patch 2

Advisory 3

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences