Vulnerability in Lightpanda-Io Browser

CVE-2026-52842

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.

EPSS: 0.002 (15.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-52842?
CVE-2026-52842 is a critical-severity vulnerability in Lightpanda-Io Browser, classified under Origin Validation Error. CVSS score: 9.3/10. Published 2026-07-15.
How severe is CVE-2026-52842?
Critical severity. CVSS v3 base score is 9.3 out of 10.