Blind SSRF via browser-side redirect bypass
Published Mar 20, 2026 · Updated Mar 20, 2026
Blind SSRF in the /download endpoint in PinchTab before 0.8.3 allows remote attackers to reach internal services via crafted URLs. validateDownloadURL() checks only the initial URL, while embedded Chromium follows attacker-controlled redirects and resource requests without revalidating each destination. The endpoint is reachable only when security.allowDownload=true, which is disabled by default; responses remain blind, but requests can trigger state changes on internal-only services.
Summary
What happened
Blind SSRF in the /download endpoint in PinchTab before 0.8.3 allows remote attackers to reach internal services via crafted URLs. validateDownloadURL() checks only the initial URL, while embedded Chromium follows attacker-controlled redirects and resource requests without revalidating each destination. The endpoint is reachable only when security.allowDownload=true, which is disabled by default; responses remain blind, but requests can trigger state changes on internal-only services.
The record
- CVE
- CVE-2026-33081
- Published
- Mar 20, 2026
- Updated
- Mar 20, 2026
- Vendor
- PinchTab
- Product
- PinchTab
- Classifications
- CWE-918, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 20, 2026CVE publishedPublication date reported by the CVE source.
- Mar 20, 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=< 0.8.3
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
- GHSA-qwxp-6qf9-wr4m reproductionproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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