Same-Origin Policy bypass via path-based at sign
Published Jul 15, 2026 · Updated Jul 15, 2026
Origin validation error in Lightpanda Browser before 0.3.1 allows remote attackers to bypass the Same-Origin Policy via a crafted URL. The URL parser's getOrigin and getHost logic searched for an at sign beyond the authority delimiter and treated a path segment as user information, assigning the fetched attacker page a victim origin. A Lightpanda-driven session must load the attacker-controlled URL; the page can then read or modify resources available to the victim origin.
Summary
What happened
Origin validation error in Lightpanda Browser before 0.3.1 allows remote attackers to bypass the Same-Origin Policy via a crafted URL. The URL parser's getOrigin and getHost logic searched for an at sign beyond the authority delimiter and treated a path segment as user information, assigning the fetched attacker page a victim origin. A Lightpanda-driven session must load the attacker-controlled URL; the page can then read or modify resources available to the victim origin.
The record
- CVE
- CVE-2026-52842
- Published
- Jul 15, 2026
- Updated
- Jul 15, 2026
- Vendor
- Lightpanda
- Product
- Lightpanda Browser
- Classifications
- CWE-346, T1189
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 15, 2026CVE publishedPublication date reported by the CVE source.
- Jul 15, 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=< 0.3.1
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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