How severe is CVE-2026-11799?

CVE-2026-11799 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-11799 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-11799?

CVE-2026-11799 primarily affects Mozilla Focus. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-11799?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-11799 have an EU (EUVD) identifier?

Yes. CVE-2026-11799 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35837.

When was CVE-2026-11799 published?

CVE-2026-11799 was published on 2026-06-09 and last updated on 2026-06-17.

CVE-2026-11799

CVE-2026-11799 is a high-severity vulnerability in Mozilla Focus with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35837
Weakness: CWE-79
Affected product: Mozilla Focus
Published: 2026-06-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-11799?: 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.
How severe is CVE-2026-11799?: CVE-2026-11799 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-11799 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-11799?: CVE-2026-11799 primarily affects Mozilla Focus. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-11799?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-11799 have an EU (EUVD) identifier?: Yes. CVE-2026-11799 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35837.
When was CVE-2026-11799 published?: CVE-2026-11799 was published on 2026-06-09 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:mozilla:focus:*:*:*:*:*:iphone_os:*:*
cpe:2.3:a:mozilla:klar:*:*:*:*:*:iphone_os:*:*

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