CVE-2010-4508

CVE-2010-4508 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

The WebSockets implementation in Mozilla Firefox 4 through 4.0 Beta 7 does not properly perform proxy upgrade negotiation, which has unspecified impact and remote attack vectors, related to an "inherent problem" with the WebSocket specification.

Frequently asked questions

What is CVE-2010-4508?
The WebSockets implementation in Mozilla Firefox 4 through 4.0 Beta 7 does not properly perform proxy upgrade negotiation, which has unspecified impact and remote attack vectors, related to an "inherent problem" with the WebSocket specification.
How severe is CVE-2010-4508?
CVE-2010-4508 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2010-4508 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-2010-4508?
CVE-2010-4508 primarily affects Mozilla Firefox. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2010-4508?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2010-4508 published?
CVE-2010-4508 was published on 2010-12-09 and last updated on 2026-06-16.

References

Affected products (6)

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