How severe is CVE-2025-27426?

CVE-2025-27426 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 low, and availability none.

Is CVE-2025-27426 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-2025-27426?

CVE-2025-27426 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-27426?

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

Does CVE-2025-27426 have an EU (EUVD) identifier?

Yes. CVE-2025-27426 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7774.

When was CVE-2025-27426 published?

CVE-2025-27426 was published on 2025-03-04 and last updated on 2026-06-17.

CVE-2025-27426

CVE-2025-27426 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-601.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-7774
Weakness: CWE-601
Affected product: Mozilla Firefox
Published: 2025-03-04
Last modified: 2026-06-17

Description

Malicious websites utilizing a server-side redirect to an internal error page could result in a spoofed website URL. This vulnerability was fixed in Firefox for iOS 136.

Frequently asked questions

What is CVE-2025-27426?: Malicious websites utilizing a server-side redirect to an internal error page could result in a spoofed website URL. This vulnerability was fixed in Firefox for iOS 136.
How severe is CVE-2025-27426?: CVE-2025-27426 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 low, and availability none.
Is CVE-2025-27426 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-2025-27426?: CVE-2025-27426 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-27426?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-27426 have an EU (EUVD) identifier?: Yes. CVE-2025-27426 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7774.
When was CVE-2025-27426 published?: CVE-2025-27426 was published on 2025-03-04 and last updated on 2026-06-17.

References

Affected products (1)

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

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