How severe is CVE-2023-34415?

CVE-2023-34415 has a CVSS 3.x base score of 6.1, 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-2023-34415 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-34415?

CVE-2023-34415 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-34415?

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

When was CVE-2023-34415 published?

CVE-2023-34415 was published on 2023-06-19 and last updated on 2026-06-17.

CVE-2023-34415

CVE-2023-34415 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.1. 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 6.1)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Mozilla Firefox
Published: 2023-06-19
Last modified: 2026-06-17

Description

When choosing a site-isolated process for a document loaded from a data: URL that was the result of a redirect, Firefox would load that document in the same process as the site that issued the redirect. This bypassed the site-isolation protections against Spectre-like attacks on sites that host an "open redirect". Firefox no longer follows HTTP redirects to data: URLs. This vulnerability affects Firefox < 114.

Frequently asked questions

What is CVE-2023-34415?: When choosing a site-isolated process for a document loaded from a data: URL that was the result of a redirect, Firefox would load that document in the same process as the site that issued the redirect. This bypassed the site-isolation protections against Spectre-like attacks on sites that host an "open redirect". Firefox no longer follows HTTP redirects to data: URLs. This vulnerability affects Firefox < 114.
How severe is CVE-2023-34415?: CVE-2023-34415 has a CVSS 3.x base score of 6.1, 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-2023-34415 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-34415?: CVE-2023-34415 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-34415?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-34415 published?: CVE-2023-34415 was published on 2023-06-19 and last updated on 2026-06-17.

References

Affected products (1)

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

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