How severe is CVE-2023-23602?

CVE-2023-23602 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 high, and availability none.

Is CVE-2023-23602 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-23602?

CVE-2023-23602 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-2023-23602?

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

When was CVE-2023-23602 published?

CVE-2023-23602 was published on 2023-06-02 and last updated on 2026-06-17.

CVE-2023-23602

CVE-2023-23602 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: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-754
Affected product: Mozilla Firefox
Published: 2023-06-02
Last modified: 2026-06-17

Description

A mishandled security check when creating a WebSocket in a WebWorker caused the Content Security Policy connect-src header to be ignored. This could lead to connections to restricted origins from inside WebWorkers. This vulnerability affects Firefox < 109, Firefox ESR < 102.7, and Thunderbird < 102.7.

Frequently asked questions

What is CVE-2023-23602?: A mishandled security check when creating a WebSocket in a WebWorker caused the Content Security Policy connect-src header to be ignored. This could lead to connections to restricted origins from inside WebWorkers. This vulnerability affects Firefox < 109, Firefox ESR < 102.7, and Thunderbird < 102.7.
How severe is CVE-2023-23602?: CVE-2023-23602 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 high, and availability none.
Is CVE-2023-23602 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-23602?: CVE-2023-23602 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-2023-23602?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-23602 published?: CVE-2023-23602 was published on 2023-06-02 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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