How severe is CVE-2025-8029?

CVE-2025-8029 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2025-8029 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-8029?

CVE-2025-8029 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-8029?

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-2025-8029 have an EU (EUVD) identifier?

Yes. CVE-2025-8029 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-22370.

When was CVE-2025-8029 published?

CVE-2025-8029 was published on 2025-07-22 and last updated on 2026-06-17.

CVE-2025-8029

CVE-2025-8029 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 8.1. 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-80.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-22370
Weakness: CWE-80
Affected product: Mozilla Firefox
Published: 2025-07-22
Last modified: 2026-06-17

Description

Thunderbird executed `javascript:` URLs when used in `object` and `embed` tags. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

Frequently asked questions

What is CVE-2025-8029?: Thunderbird executed `javascript:` URLs when used in `object` and `embed` tags. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.
How severe is CVE-2025-8029?: CVE-2025-8029 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2025-8029 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-8029?: CVE-2025-8029 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-8029?: 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-2025-8029 have an EU (EUVD) identifier?: Yes. CVE-2025-8029 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-22370.
When was CVE-2025-8029 published?: CVE-2025-8029 was published on 2025-07-22 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

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