Privileged session hijacking via unchecked HTML upload
Published Sep 24, 2025 · Updated Sep 24, 2025
Stored XSS in Horilla HRMS before 1.4.0 allows remote attackers to steal privileged session cookies through uploaded HTML files. The reimbursement upload flow enforces file-type validation only in browser code, so a crafted request stores executable HTML without a server-side check. Exploitation requires upload access and a privileged user to view the file; the resulting cookie can be reused to impersonate that user.
Summary
What happened
Stored XSS in Horilla HRMS before 1.4.0 allows remote attackers to steal privileged session cookies through uploaded HTML files. The reimbursement upload flow enforces file-type validation only in browser code, so a crafted request stores executable HTML without a server-side check. Exploitation requires upload access and a privileged user to view the file; the resulting cookie can be reused to impersonate that user.
The record
- CVE
- CVE-2025-59524
- Published
- Sep 24, 2025
- Updated
- Sep 24, 2025
- Vendor
- Cybrosys Technologies
- Product
- Horilla HRMS
- Classifications
- CWE-434, CWE-79, T1539
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 24, 2025CVE publishedPublication date reported by the CVE source.
- Sep 24, 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=< 1.4.0
What conditions does exploitation require?
What is affected?
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
- Horilla reimbursement upload stored-XSS proof of conceptproof 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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