Stored script execution via unescaped client title
Published Feb 18, 2026 · Updated Feb 18, 2026
Stored XSS in InvoicePlane 1.7.0 allows remote authenticated users to run JavaScript in another user's browser via a custom client title. The format_client() helper returns nonstandard custom titles without HTML escaping, and view_sumex.php echoes that output into the invoice link. Exploitation requires client and invoice management privileges, enabled Sumex features, a specially named invoice group, and a user who views the crafted invoice.
Summary
What happened
Stored XSS in InvoicePlane 1.7.0 allows remote authenticated users to run JavaScript in another user's browser via a custom client title. The format_client() helper returns nonstandard custom titles without HTML escaping, and view_sumex.php echoes that output into the invoice link. Exploitation requires client and invoice management privileges, enabled Sumex features, a specially named invoice group, and a user who views the crafted invoice.
The record
- CVE
- CVE-2026-26281
- Published
- Feb 18, 2026
- Updated
- Feb 18, 2026
- Vendor
- InvoicePlane
- Product
- InvoicePlane
- Classifications
- CWE-79, T1059.007
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 18, 2026CVE publishedPublication date reported by the CVE source.
- Feb 18, 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== 1.7.0
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
- GitHub advisory Sumex stored-XSS reproductionproof of concept · demonstrated
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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