CVSS v3
9.8
CRITICAL
EPSS Score
1.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Faye (NPM, RubyGem) versions greater than 0.5.0 and before 1.0.4, 1.1.3 and 1.2.5, has the potential for authentication bypass in the extension system. The vulnerability allows any client to bypass checks put in place by server-side extensions, by appending extra segments to the message channel. It is patched in versions 1.0.4, 1.1.3 and 1.2.5.
Technical details
- Published
- 2020-04-29
Frequently asked questions
What is CVE-2020-11020?
Faye (NPM, RubyGem) versions greater than 0.5.0 and before 1.0.4, 1.1.3 and 1.2.5, has the potential for authentication bypass in the extension system. The vulnerability allows any client to bypass checks put in place by server-side extensions, by appending extra segments to the message channel. It is patched in versions 1.0.4, 1.1.3 and 1.2.5.
Is CVE-2020-11020 actively exploited?
Active exploitation of CVE-2020-11020 has not been confirmed. Its EPSS score was 1.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2020-11020?
CVE-2020-11020 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2020-11020 affecting your environment?
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