CleanTalk Plugin up to 6.86 on WordPress shortcode injection

Summaryinfo

A vulnerability was found in CleanTalk Plugin up to 6.86. It has been rated as critical. Affected by this issue is some unknown functionality of the component shortcode Handler. This manipulation causes injection. This vulnerability is handled as CVE-2026-19855. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in CleanTalk Plugin up to 6.86 and classified as critical. Affected by this vulnerability is an unknown function of the component shortcode Handler. The manipulation with an unknown input leads to a injection vulnerability. The CWE definition for the vulnerability is CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The CleanTalk WordPress plugin before 6.87 does not prevent unauthenticated, user-supplied comment content from being passed to WordPress's shortcode engine, allowing any visitor to have arbitrary shortcodes registered on the site executed server-side and rendered to every subsequent visitor of the page.

It is possible to read the advisory at wpscan.com. This vulnerability is known as CVE-2026-19855 since 08/14/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1055 according to MITRE ATT&CK.

Upgrading to version 6.87 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• WordPress Plugin

Name

• CleanTalk Plugin

Version

• 6.0
• 6.1
• 6.2
• 6.3
• 6.4
• 6.5
• 6.6
• 6.7
• 6.8
• 6.9
• 6.10
• 6.11
• 6.12
• 6.13
• 6.14
• 6.15
• 6.16
• 6.17
• 6.18
• 6.19
• 6.20
• 6.21
• 6.22
• 6.23
• 6.24
• 6.25
• 6.26
• 6.27
• 6.28
• 6.29
• 6.30
• 6.31
• 6.32
• 6.33
• 6.34
• 6.35
• 6.36
• 6.37
• 6.38
• 6.39
• 6.40
• 6.41
• 6.42
• 6.43
• 6.44
• 6.45
• 6.46
• 6.47
• 6.48
• 6.49
• 6.50
• 6.51
• 6.52
• 6.53
• 6.54
• 6.55
• 6.56
• 6.57
• 6.58
• 6.59
• 6.60
• 6.61
• 6.62
• 6.63
• 6.64
• 6.65
• 6.66
• 6.67
• 6.68
• 6.69
• 6.70
• 6.71
• 6.72
• 6.73
• 6.74
• 6.75
• 6.76
• 6.77
• 6.78
• 6.79
• 6.80
• 6.81
• 6.82
• 6.83
• 6.84
• 6.85
• 6.86

CPE 2.3info

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CPE 2.2info

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