Stored XSS via unvalidated settings parameter
Published Mar 21, 2026 · Updated Mar 21, 2026
Stored XSS in Frank Koenen login_register 1.2.0 and earlier allows remote attackers to inject scripts through a forged settings request. The settings handler accepts login_register_login_post without nonce validation, sanitization, or escaping before storing and rendering it. Exploitation requires an administrator to submit the forged request, after which the stored script executes when an injected page is viewed.
Summary
What happened
Stored XSS in Frank Koenen login_register 1.2.0 and earlier allows remote attackers to inject scripts through a forged settings request. The settings handler accepts login_register_login_post without nonce validation, sanitization, or escaping before storing and rendering it. Exploitation requires an administrator to submit the forged request, after which the stored script executes when an injected page is viewed.
The record
- CVE
- CVE-2026-1503
- Published
- Mar 21, 2026
- Updated
- Mar 21, 2026
- Vendor
- Frank Koenen
- Product
- login_register
- Classifications
- CWE-352, T1204.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 21, 2026CVE publishedPublication date reported by the CVE source.
- Mar 21, 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?
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- Affected versionversion=* <=1.2.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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