How severe is CVE-2023-4582?

CVE-2023-4582 has a CVSS 3.x base score of 8.8, 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 high.

Is CVE-2023-4582 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-4582?

CVE-2023-4582 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-2023-4582?

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.

When was CVE-2023-4582 published?

CVE-2023-4582 was published on 2023-09-11 and last updated on 2026-06-17.

CVE-2023-4582

CVE-2023-4582 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 8.8. 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-120.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Mozilla Firefox
Published: 2023-09-11
Last modified: 2026-06-17

Description

Due to large allocation checks in Angle for glsl shaders being too lenient a buffer overflow could have occurred when allocating too much private shader memory on mac OS. *This bug only affects Firefox on macOS. Other operating systems are unaffected.* This vulnerability affects Firefox < 117, Firefox ESR < 115.2, and Thunderbird < 115.2.

Frequently asked questions

What is CVE-2023-4582?: Due to large allocation checks in Angle for glsl shaders being too lenient a buffer overflow could have occurred when allocating too much private shader memory on mac OS. *This bug only affects Firefox on macOS. Other operating systems are unaffected.* This vulnerability affects Firefox < 117, Firefox ESR < 115.2, and Thunderbird < 115.2.
How severe is CVE-2023-4582?: CVE-2023-4582 has a CVSS 3.x base score of 8.8, 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 high.
Is CVE-2023-4582 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-4582?: CVE-2023-4582 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-2023-4582?: 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.
When was CVE-2023-4582 published?: CVE-2023-4582 was published on 2023-09-11 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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