Critical severity · published Jul 15, 2026
CVE-2026-52842
Lightpanda:URL parser misidentifies page origin for URLs containing @ in the path - Same-Origin Policy bypass
9.3
CVSS
0.2%
EPSS
No
On KEV
Description
Lightpanda is a headless browser designed for AI and automation. Prior to 0.3.1, Lightpanda searched for @ across the entire URL string instead of only the authority component when computing a page origin, so a URL such as `http://attacker.com/@victim.com/` was fetched from attacker.com but treated as `http://victim.com`, allowing a complete Same-Origin Policy bypass. This issue is fixed in version 0.3.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BR
browser · lightpanda-io
< 0.3.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-52842
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-52842
github.com
https://github.com/lightpanda-io/browser/commit/0588cc374d4af9687cf6f45a7d52f7af04bbacfb
github.com
https://github.com/lightpanda-io/browser/pull/1998
github.com
https://github.com/lightpanda-io/browser/releases/tag/0.3.1
github.com
https://github.com/lightpanda-io/browser/security/advisories/GHSA-mq6p-m9cc-q432
More from browser
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