Stored XSS via unescaped memo post metadata
Published Jun 10, 2026 · Updated Jun 10, 2026
Stored XSS in MW WP Form 5.1.3 and earlier allows remote authenticated users with Editor access to inject scripts via the memo field. The plugin writes the memo value directly with update_post_meta() and renders it in a textarea without sufficient escaping, bypassing WordPress content filtering. Editor-level access is required; viewing the affected inquiry-data page executes the stored script in the viewer's browser.
Summary
What happened
Stored XSS in MW WP Form 5.1.3 and earlier allows remote authenticated users with Editor access to inject scripts via the memo field. The plugin writes the memo value directly with update_post_meta() and renders it in a textarea without sufficient escaping, bypassing WordPress content filtering. Editor-level access is required; viewing the affected inquiry-data page executes the stored script in the viewer's browser.
The record
- CVE
- CVE-2026-8853
- Published
- Jun 10, 2026
- Updated
- Jun 10, 2026
- Vendor
- 株式会社Webの相談所
- Product
- MW WP Form
- Classifications
- CWE-79, T1203
- Attack vector
- network
- Privileges
- authenticated
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 <=5.1.3
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
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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