Contributor-level stored XSS via unescaped shortcode attribute
Published Jan 30, 2023 · Updated Mar 27, 2025
Stored XSS in Paid Memberships Pro Register Helper before 1.8.1 allows remote authenticated users to execute script in administrators' browsers. The pmpro_signup shortcode outputs the button attribute into page markup without validation or escaping, so an injected event handler is stored with the post. Contributor-level access and an administrator viewing or interacting with the rendered page are required; the script runs with that administrator's site privileges.
Summary
What happened
Stored XSS in Paid Memberships Pro Register Helper before 1.8.1 allows remote authenticated users to execute script in administrators' browsers. The pmpro_signup shortcode outputs the button attribute into page markup without validation or escaping, so an injected event handler is stored with the post. Contributor-level access and an administrator viewing or interacting with the rendered page are required; the script runs with that administrator's site privileges.
The record
- CVE
- CVE-2022-4831
- Published
- Jan 30, 2023
- Updated
- Mar 27, 2025
- Vendor
- Paid Memberships Pro
- Product
- Register Helper
- Classifications
- CWE-79, CAPEC-592, T1059.007
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 30, 2023CVE publishedPublication date reported by the CVE source.
- Mar 27, 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 <1.8.1
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
- pmpro_signup button-attribute stored-XSS shortcodeproof of concept · validated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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