Subscriber-level option overwrite via unchecked AJAX callback
Published Oct 31, 2023 · Updated Apr 23, 2025
Missing authorization in Campaign Monitor Forms by Optin Cat before 2.5.6 allows remote authenticated users to overwrite site options. The fca_eoi_dismiss AJAX callback passes the attacker-controlled option parameter to update_option() with the value true without a capability check. Subscriber access and at least 25 recorded conversions are required to obtain the notice nonce; overwriting critical options can interrupt the site.
Summary
What happened
Missing authorization in Campaign Monitor Forms by Optin Cat before 2.5.6 allows remote authenticated users to overwrite site options. The fca_eoi_dismiss AJAX callback passes the attacker-controlled option parameter to update_option() with the value true without a capability check. Subscriber access and at least 25 recorded conversions are required to obtain the notice nonce; overwriting critical options can interrupt the site.
The record
- CVE
- CVE-2023-5098
- Published
- Oct 31, 2023
- Updated
- Apr 23, 2025
- Vendor
- Fatcat Apps
- Product
- Campaign Monitor Forms by Optin Cat
- Classifications
- CWE-284, T1499
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 31, 2023CVE publishedPublication date reported by the CVE source.
- Apr 23, 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.
- Affected versionversion=0 <2.5.6
What conditions does exploitation require?
What is affected?
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.
Public exploit references
- WPScan fca_eoi_dismiss proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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