How severe is CVE-2023-34414?

CVE-2023-34414 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2023-34414 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-34414?

CVE-2023-34414 primarily affects Mozilla Firefox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-34414?

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

When was CVE-2023-34414 published?

CVE-2023-34414 was published on 2023-06-19 and last updated on 2026-06-17.

CVE-2023-34414

CVE-2023-34414 is a low-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 3.1. 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-295.

Key facts

Severity: Low (CVSS 3.x base score 3.1)
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Mozilla Firefox
Published: 2023-06-19
Last modified: 2026-06-17

Description

The error page for sites with invalid TLS certificates was missing the activation-delay Firefox uses to protect prompts and permission dialogs from attacks that exploit human response time delays. If a malicious page elicited user clicks in precise locations immediately before navigating to a site with a certificate error and made the renderer extremely busy at the same time, it could create a gap between when the error page was loaded and when the display actually refreshed. With the right timing the elicited clicks could land in that gap and activate the button that overrides the certificate error for that site. This vulnerability affects Firefox ESR < 102.12, Firefox < 114, and Thunderbird < 102.12.

Frequently asked questions

What is CVE-2023-34414?: The error page for sites with invalid TLS certificates was missing the activation-delay Firefox uses to protect prompts and permission dialogs from attacks that exploit human response time delays. If a malicious page elicited user clicks in precise locations immediately before navigating to a site with a certificate error and made the renderer extremely busy at the same time, it could create a gap between when the error page was loaded and when the display actually refreshed. With the right timing the elicited clicks could land in that gap and activate the button that overrides the certificate error for that site. This vulnerability affects Firefox ESR < 102.12, Firefox < 114, and Thunderbird < 102.12.
How severe is CVE-2023-34414?: CVE-2023-34414 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2023-34414 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-34414?: CVE-2023-34414 primarily affects Mozilla Firefox. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-34414?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-34414 published?: CVE-2023-34414 was published on 2023-06-19 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

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