VulnerabilityPublished 24 Jun 2026Updated 25 Jun 2026

CVE-2026-10552: Blue Captcha (WordPress plugin) · Cross-Site Request Forgery (CSRF)

Affects Blue Captcha (WordPress plugin)Source CVE Database V5

Compare

Not known to be exploited · CVSS 4.3 Medium.

Data as of 5 Nov 2026, 23:24 UTC

CVSS 3.1 base score

4.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: None
Integrity: Low
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
jotisBlue Captcha	Affected <=2.0.1	Fixed in–

AI-suggested

Until a fix is available, administrators should avoid clicking on untrusted links while logged into the WordPress admin panel. Monitoring for suspicious changes to the plugin or its logs may help detect exploitation attempts. Implementing additional security controls such as web application firewalls or custom nonce verification could mitigate risk.

Description

The Blue Captcha plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to and including 2.0.1. This is due to missing or incorrect nonce validation on the main admin panel (blcap_main_page) and on the Hall of Shame and Log subpages, which accept a 'blcap_action' / 'action' parameter from $_REQUEST and perform destructive operations (plugin uninstall via blcap_uninstall(), log deletion via blcap_delete_logs(), Hall of Shame deletion via blcap_delete_ip_db(), and adding IPs to the banned list via update_option('blcap_settings')) with no wp_verify_nonce(), check_admin_referer(), or check_ajax_referer() calls anywhere in the codebase. This makes it possible for unauthenticated attackers to uninstall the plugin, delete audit logs, remove Hall of Shame entries, and add arbitrary IP addresses to the block list via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Impact

An attacker can cause an administrator to unknowingly uninstall the Blue Captcha plugin, delete audit logs, remove Hall of Shame entries, or add arbitrary IP addresses to the block list. This compromises the integrity and availability of the plugin's security features and audit data, potentially weakening the site's defense against malicious traffic. There is no direct confidentiality impact reported.

Summary

CVE-2026-10552 describes a CSRF vulnerability in the jotis Blue Captcha WordPress plugin versions up to and including 2.0.1. The plugin's main admin panel and certain subpages accept 'blcap_action' or 'action' parameters from $_REQUEST and execute destructive functions like plugin uninstallation, log deletion, Hall of Shame entry removal, and IP banning without any nonce verification (no wp_verify_nonce(), check_admin_referer(), or check_ajax_referer() calls). This lack of proper nonce validation enables unauthenticated attackers to perform these actions by tricking an administrator into clicking a crafted link or visiting a malicious page.

CWE-352Cross-Site Request Forgery (opens in a new tab)
Compound weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #3OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Implementation
Ensure that the application is free of cross-site scripting issues (CWE-79), because most CSRF defenses can be bypassed using attacker-controlled script.
Architecture and Design
Generate a unique nonce for each form, place the nonce into the form, and verify the nonce upon receipt of the form. Be sure that the nonce is not predictable (CWE-330).
OWASP Cheat Sheets
REST Assessment (opens in a new tab)
REST Security (opens in a new tab)
Cross-Site Request Forgery Prevention (opens in a new tab)
Authorization Testing Automation (opens in a new tab)
Insecure Direct Object Reference Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V13.2.3 (opens in a new tab)
V4.2.2 (opens in a new tab)
V13.3.2 (opens in a new tab)
Attack patterns
JSON Hijacking (aka JavaScript Hijacking) (opens in a new tab)
Cross-Domain Search Timing (opens in a new tab)
Cross Site Identification (opens in a new tab)
Cross Site Request Forgery (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 1 Jul 2026, 22:42 UTC

WeaknessesCWE-352

Technical details

References

Community reviews

Related threats