How severe is CVE-2024-0743?

CVE-2024-0743 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-0743 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-0743?

CVE-2024-0743 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-0743?

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-2024-0743 have an EU (EUVD) identifier?

Yes. CVE-2024-0743 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-16532.

When was CVE-2024-0743 published?

CVE-2024-0743 was published on 2024-01-23 and last updated on 2026-06-17.

CVE-2024-0743

CVE-2024-0743 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 7.5. 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-252.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-16532
Weakness: CWE-252
Affected product: Mozilla Firefox
Published: 2024-01-23
Last modified: 2026-06-17

Description

An unchecked return value in TLS handshake code could have caused a potentially exploitable crash. This vulnerability affects Firefox < 122, Firefox ESR < 115.9, and Thunderbird < 115.9.

Frequently asked questions

What is CVE-2024-0743?: An unchecked return value in TLS handshake code could have caused a potentially exploitable crash. This vulnerability affects Firefox < 122, Firefox ESR < 115.9, and Thunderbird < 115.9.
How severe is CVE-2024-0743?: CVE-2024-0743 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-0743 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-0743?: CVE-2024-0743 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-0743?: 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-2024-0743 have an EU (EUVD) identifier?: Yes. CVE-2024-0743 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-16532.
When was CVE-2024-0743 published?: CVE-2024-0743 was published on 2024-01-23 and last updated on 2026-06-17.

References

Affected products (1)

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

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