Stored XSS via PDF MIME confusion
Published Aug 17, 2026 · Updated Aug 18, 2026
Stored XSS in Pandora before 1.12.6 allows attackers to execute script in a victim browser via crafted PDF download responses. In website/web/init.py, the api_task_download handler passed task.file.path to Flask send_file without fixing the response MIME type, attachment disposition, or download filename, letting attacker-controlled filename metadata make a stored PDF polyglot render as active HTML or another executable web format. Exploitation requires the ability to submit the malicious file and a victim who can access that analysis and open its PDF download link; script then runs in the Pandora origin and can read data or perform actions with the victim's session.
Summary
What happened
Stored XSS in Pandora before 1.12.6 allows attackers to execute script in a victim browser via crafted PDF download responses. In website/web/init.py, the api_task_download handler passed task.file.path to Flask send_file without fixing the response MIME type, attachment disposition, or download filename, letting attacker-controlled filename metadata make a stored PDF polyglot render as active HTML or another executable web format. Exploitation requires the ability to submit the malicious file and a victim who can access that analysis and open its PDF download link; script then runs in the Pandora origin and can read data or perform actions with the victim's session.
The record
- CVE
- CVE-2026-75529
- Published
- Aug 17, 2026
- Updated
- Aug 18, 2026
- Vendor
- Pandora analysis
- Product
- Pandora
- Classifications
- CWE-79, CAPEC-209, T1185
- Attack vector
- network
- Privileges
- Unavailable
Timeline
How it unfolded
- Aug 17, 2026CVE publishedPublication date reported by the CVE source.
- Aug 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=0 <=1.12.5
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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