How severe is CVE-2024-1556?

CVE-2024-1556 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 user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-1556 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-1556?

CVE-2024-1556 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-1556?

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

Does CVE-2024-1556 have an EU (EUVD) identifier?

Yes. CVE-2024-1556 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-17303.

When was CVE-2024-1556 published?

CVE-2024-1556 was published on 2024-02-20 and last updated on 2026-06-17.

CVE-2024-1556

CVE-2024-1556 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.5. 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-754.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-17303
Weakness: CWE-754
Affected product: Mozilla Firefox
Published: 2024-02-20
Last modified: 2026-06-17

Description

The incorrect object was checked for NULL in the built-in profiler, potentially leading to invalid memory access and undefined behavior. *Note:* This issue only affects the application when the profiler is running. This vulnerability affects Firefox < 123.

Frequently asked questions

What is CVE-2024-1556?: The incorrect object was checked for NULL in the built-in profiler, potentially leading to invalid memory access and undefined behavior. *Note:* This issue only affects the application when the profiler is running. This vulnerability affects Firefox < 123.
How severe is CVE-2024-1556?: CVE-2024-1556 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 user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-1556 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-1556?: CVE-2024-1556 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-1556?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-1556 have an EU (EUVD) identifier?: Yes. CVE-2024-1556 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-17303.
When was CVE-2024-1556 published?: CVE-2024-1556 was published on 2024-02-20 and last updated on 2026-06-17.

References

Affected products (1)

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

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