CVE-2021-43353Network attack vector

Stored XSS via missing settings nonce validation

Published Jan 18, 2022 · Updated Jan 31, 2025

Cross-site request forgery in the Crisp Live Chat WordPress plugin 0.31 and earlier allows remote attackers to inject stored web scripts. The crisp_plugin_settings_page function in crisp.php accepts state-changing settings requests without validating a WordPress nonce. Exploitation requires a logged-in administrator to interact with attacker-controlled content, after which the injected script executes in the plugin's administrative context.

CVSS severity8.8
High
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site request forgery in the Crisp Live Chat WordPress plugin 0.31 and earlier allows remote attackers to inject stored web scripts. The crisp_plugin_settings_page function in crisp.php accepts state-changing settings requests without validating a WordPress nonce. Exploitation requires a logged-in administrator to interact with attacker-controlled content, after which the injected script executes in the plugin's administrative context.

The record

CVE
CVE-2021-43353
Published
Jan 18, 2022
Updated
Jan 31, 2025
Vendor
Crisp
Product
Crisp Live Chat
Classifications
CWE-352
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 18, 2022CVE publishedPublication date reported by the CVE source.
  2. Jan 31, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.31 <=0.31

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Crisp · Crisp Live Chatversion=0.31 <=0.31

Published CVSS scores

6.8NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.8WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-352Cross-Site Request Forgery (CSRF)

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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