CVE-2023-23602mediumCWE-754

CVE-2023-23602: medium-severity vulnerability in Mozilla Firefox

Content Security Policy wasn't being correctly applied to WebSockets in WebWorkers

Published 02 Jun 2023 · Updated 18 Dec 2025

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.6%

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.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Affected products

Mozilla · Firefox Mozilla · Firefox ESR Mozilla · Thunderbird

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References

https://bugzilla.mozilla.org/show_bug.cgi?id=1800890 https://www.mozilla.org/security/advisories/mfsa2023-01/https://www.mozilla.org/security/advisories/mfsa2023-02/https://www.mozilla.org/security/advisories/mfsa2023-03/