Lightpanda:URL parser misidentifies page origin for URLs containing @ in the path - Same-Origin Policy bypass
Priority MEDIUM 42CWE-346Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-346.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00246 15th percentileScored 2026-11-07
Fix Fixed browser (lightpanda-io): 0.3.1
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| lightpanda-io | browser | before 0.3.1 | 0.3.1 | Patch available | CNA |
- browser Vendorlightpanda-io Affected before 0.3.1 Fixed in 0.3.1 Patch available CNA
Remediation
- Fix · CNA browser (lightpanda-io) Fixed in 0.3.1
Timeline
- 2026-10-02 Threatist record created from CVE-2026-52842
References
More lightpanda-io vulnerabilities
- TI-2026-37951 Lightpanda: fetch() and XMLHttpRequest attach session cookies to cross-origin requests regardless of credentials mode CVSS 3.1CRITICAL 9.3
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences