Unauthenticated stored XSS via email-encoder shortcode bypass
Published Jun 10, 2026 · Updated Jun 10, 2026
Stored XSS in Anti-Spam by CleanTalk before 6.79 allows remote attackers to inject scripts through approved WordPress comments. The email/contact encoder accepts an apbct_encode_data shortcode whose closing delimiter can be placed inside an HTML attribute, allowing unsanitized trailing markup to survive comment rendering. Exploitation requires a valid CleanTalk access key, the encoder active, and the crafted comment approved and viewed; JavaScript then runs in the viewer's browser, including an administrator's session.
Summary
What happened
Stored XSS in Anti-Spam by CleanTalk before 6.79 allows remote attackers to inject scripts through approved WordPress comments. The email/contact encoder accepts an apbct_encode_data shortcode whose closing delimiter can be placed inside an HTML attribute, allowing unsanitized trailing markup to survive comment rendering. Exploitation requires a valid CleanTalk access key, the encoder active, and the crafted comment approved and viewed; JavaScript then runs in the viewer's browser, including an administrator's session.
The record
- CVE
- CVE-2026-8071
- Published
- Jun 10, 2026
- Updated
- Jun 10, 2026
- Vendor
- CleanTalk
- Product
- Anti-Spam by CleanTalk
- Classifications
- CWE-79, T1059.007
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 10, 2026CVE publishedPublication date reported by the CVE source.
- Jun 10, 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 <6.79
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
- WPScan comment-shortcode proof of conceptproof of concept · validated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
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