Unauthenticated site takeover via zero-key type juggling
Published Jan 11, 2024 · Updated Apr 8, 2026
Authorization bypass in Fullworks Plugins Post SMTP 2.8.7 and earlier allows remote attackers to read email logs through its mobile REST API. Post_SMTP_Mobile_Rest_API::connect_app deletes the submitted auth token, leaves the stored nonce empty, and loosely accepts a zero auth key before replacing the API key. No account or user interaction is required; retrieved password-reset messages allow an administrator password change and site takeover.
Summary
What happened
Authorization bypass in Fullworks Plugins Post SMTP 2.8.7 and earlier allows remote attackers to read email logs through its mobile REST API. Post_SMTP_Mobile_Rest_API::connect_app deletes the submitted auth token, leaves the stored nonce empty, and loosely accepts a zero auth key before replacing the API key. No account or user interaction is required; retrieved password-reset messages allow an administrator password change and site takeover.
The record
- CVE
- CVE-2023-6875
- Published
- Jan 11, 2024
- Updated
- Apr 8, 2026
- Vendor
- Fullworks Plugins
- Product
- Post SMTP
- Classifications
- CWE-639, T1078
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 11, 2024CVE publishedPublication date reported by the CVE source.
- Apr 8, 2026Record 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 <=2.8.7
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- WordPress POST SMTP Mailer 2.8.7 Authorization Bypass and Cross-Site Scriptingfunctional · validated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- Wordfence recorded attacks targeting the Post SMTP authorization bypass during 2024reported exploitation
Technologies
Your stack
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Your stack
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