CVE-2022-24880

Status: ModifiedMedium (5.3)—

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Base score: 5.3

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.21%
Percentile among all scored CVEs: 67
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Flask-session-captcha Project — Flask-session-captcha

CWEs

CWE-253, CWE-394, CWE-754
CWE-754

References

Raw JSON (NVD)

Show

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