How severe is CVE-2026-9078?

CVE-2026-9078 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability low.

Is CVE-2026-9078 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-9078?

CVE-2026-9078 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-9078?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-9078 have an EU (EUVD) identifier?

Yes. CVE-2026-9078 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31693.

When was CVE-2026-9078 published?

CVE-2026-9078 was published on 2026-05-25 and last updated on 2026-06-17.

CVE-2026-9078

CVE-2026-9078 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 5.4. 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-451.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31693
Weakness: CWE-451
Affected product: Mozilla Firefox
Published: 2026-05-25
Last modified: 2026-06-17

Description

Firefox for iOS displayed specially crafted right-to-left (RTL) and internationalized domain names (IDNs) incorrectly in link preview UI surfaces. A crafted RTL hostname could visually reorder portions of the displayed domain, causing attacker-controlled sites to appear as trusted origins. This vulnerability was fixed in Firefox for iOS 151.1.

Frequently asked questions

What is CVE-2026-9078?: Firefox for iOS displayed specially crafted right-to-left (RTL) and internationalized domain names (IDNs) incorrectly in link preview UI surfaces. A crafted RTL hostname could visually reorder portions of the displayed domain, causing attacker-controlled sites to appear as trusted origins. This vulnerability was fixed in Firefox for iOS 151.1.
How severe is CVE-2026-9078?: CVE-2026-9078 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability low.
Is CVE-2026-9078 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-9078?: CVE-2026-9078 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-9078?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-9078 have an EU (EUVD) identifier?: Yes. CVE-2026-9078 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31693.
When was CVE-2026-9078 published?: CVE-2026-9078 was published on 2026-05-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:iphone_os:*:*

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