CWEweakness

CWE-804 Guessable CAPTCHA

Official page ↗
Abstraction
Base
Structure
Simple
Status
Incomplete
Languages
Not Language-Specific
CWE version
5.0

Description

The product uses a CAPTCHA challenge, but the challenge can be guessed or automatically recognized by a non-human actor.

Common consequences

• Access Control, Other: Bypass Protection Mechanism, Other — When authorization, authentication, or another protection mechanism relies on CAPTCHA entities to ensure that only human actors can access certain functionality, then an automated attacker such as a bot may access the restricted functionality by guessing the CAPTCHA.

Observed examples

• CVE-2022-4036: Chain: appointment booking app uses a weak hash (CWE-328) for generating a CAPTCHA, making it guessable (CWE-804)

Related

Observed example · CVE (1)

  • CVE-2022-4036 The Appointment Hour Booking plugin for WordPress is vulnerable to CAPTCHA bypass in versions up to, and including, 1.3.72. vulnerability

Child of · CWE (2)

  • CWE-1390 Weak Authentication weakness
  • CWE-863 Incorrect Authorization weakness

Referenced by CVE · weakness (20)

  • CVE-2026-112067 The extension hides the correct answer to each CAPTCHA inside the image data of the CAPTCHA itself. vulnerability
  • CVE-2026-111278 NivoCart through 2.5.1 contains a CAPTCHA bypass vulnerability that allows unauthenticated attackers to defeat form protection because the… vulnerability
  • CVE-2024-23566 HCL Aftermarket EPC is vulnerable to brute force attacks since application doesn’t have captcha implemented. vulnerability
  • CVE-2024-23567 HCL Aftermarket EPC is affected by Sensitive Information in GET method & in URL which allows application to pass sensitive data via URL… vulnerability
  • CVE-2026-13082 GD::SecurityImage versions through 1.75 for Perl use rand to generate secrets. vulnerability
  • CVE-2026-49953 Discuz! vulnerability
  • CVE-2026-40935 WWBN AVideo is an open source video platform. vulnerability
  • CVE-2025-70129 If the anti spam-captcha functionality in PluXml versions 5.8.22 and earlier is enabled, a captcha challenge is generated with a format… vulnerability
  • CVE-2026-27411 Guessable CAPTCHA vulnerability in jp-secure SiteGuard WP Plugin siteguard allows Functionality Bypass.This issue affects SiteGuard WP… vulnerability
  • CVE-2025-10423 A vulnerability was found in newbee-mall 1.0. vulnerability
  • CVE-2025-8546 A vulnerability, which was classified as problematic, was found in atjiu pybbs up to 6.0.0. vulnerability
  • CVE-2025-50850 An issue was discovered in CS Cart 4.18.3 allows the vendor login functionality lacks essential security controls such as CAPTCHA… vulnerability
  • CVE-2025-40916 Mojolicious::Plugin::CaptchaPNG version 1.05 for Perl uses a weak random number source for generating the captcha. vulnerability
  • CVE-2025-32036 DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. vulnerability
  • CVE-2025-1262 The Advanced Google reCaptcha plugin for WordPress is vulnerable to CAPTCHA Bypass in versions up to, and including, 1.27 . vulnerability
  • CVE-2024-30540 Guessable CAPTCHA vulnerability in Guido VS Contact Form allows Functionality Bypass.This issue affects VS Contact Form: from n/a through… vulnerability
  • CVE-2024-31295 Guessable CAPTCHA vulnerability in BestWebSoft Captcha by BestWebSoft allows Functionality Bypass.This issue affects Captcha by… vulnerability
  • CVE-2023-6963 The Getwid – Gutenberg Blocks plugin for WordPress is vulnerable to CAPTCHA Bypass in versions up to, and including, 2.0.4. vulnerability
  • CVE-2022-4036 The Appointment Hour Booking plugin for WordPress is vulnerable to CAPTCHA bypass in versions up to, and including, 1.3.72. vulnerability
  • CVE-2022-1801 The Very Simple Contact Form WordPress plugin before 11.6 exposes the solution to the captcha in the rendered contact form, both as hidden… vulnerability

Referenced by CWE · can precede (1)

  • CWE-330 Use of Insufficiently Random Values weakness