CVE-2026-52843criticalCWE-346

CVE-2026-52843: critical vulnerability in lightpanda-io browser

Lightpanda: fetch() and XMLHttpRequest attach session cookies to cross-origin requests regardless of credentials mode

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.3epss 0.2%
Lightpanda is a headless browser designed for AI and automation. Prior to 0.2.9, Lightpanda fetch() and XMLHttpRequest unconditionally attached session cookies to every HTTP request, ignoring credentials: omit, credentials: same-origin, credentials: include, and XMLHttpRequest.withCredentials, allowing an attacker-controlled origin in a Lightpanda session to issue authenticated cross-origin requests against a victim origin. This issue is fixed in version 0.2.9.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
Affected products
lightpanda-io · browser
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CVE-2026-52842CRITICALLightpanda:URL parser misidentifies page origin for URLs containing @ in the path - Same-Origin Policy bypassEPSS 0.2%