CVE-2026-52843

CRITICAL 9.3

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

CVSS Score

9.3

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-346
Vendor	lightpanda-io
Product	browser
Published	Jul 15, 2026
Last Updated	Jul 15, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

Affected Versions

lightpanda-io / browser

< 0.2.9

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/lightpanda-io/browser/security/advisories/GHSA-36mm-v3c2-24cc github.com: https://github.com/lightpanda-io/browser/pull/2155 github.com: https://github.com/lightpanda-io/browser/commit/2cdaac780bed65db98bbb6ed2ad5bc6011863c76 github.com: https://github.com/lightpanda-io/browser/releases/tag/0.2.9