How severe is CVE-2025-0242?

CVE-2025-0242 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-0242 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-0242?

CVE-2025-0242 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-2025-0242?

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

Does CVE-2025-0242 have an EU (EUVD) identifier?

Yes. CVE-2025-0242 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-1574.

When was CVE-2025-0242 published?

CVE-2025-0242 was published on 2025-01-07 and last updated on 2026-06-17.

CVE-2025-0242

CVE-2025-0242 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.5. Its EPSS exploit-prediction score of 13% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 13% (96th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-1574
Weakness: CWE-787
Affected product: Mozilla Firefox
Published: 2025-01-07
Last modified: 2026-06-17

Description

Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 115.18, Firefox ESR 128.5, Thunderbird 115.18, and Thunderbird 128.5. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Firefox ESR 115.19, Thunderbird 134, and Thunderbird 128.6.

Frequently asked questions

What is CVE-2025-0242?: Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 115.18, Firefox ESR 128.5, Thunderbird 115.18, and Thunderbird 128.5. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Firefox ESR 115.19, Thunderbird 134, and Thunderbird 128.6.
How severe is CVE-2025-0242?: CVE-2025-0242 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-0242 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-0242?: CVE-2025-0242 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-2025-0242?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-0242 have an EU (EUVD) identifier?: Yes. CVE-2025-0242 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-1574.
When was CVE-2025-0242 published?: CVE-2025-0242 was published on 2025-01-07 and last updated on 2026-06-17.

References

Affected products (3)

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

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