CVE-2020-11020

Name: CVE-2020-11020
Creator: NVD / NIST
Published: 2020-04-29T18:15:13.36+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.50%

Last modified Jun 17, 2026

CVE-2020-11020 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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. EPSS estimates a 1.50% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

1.50%

71.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Faye Project	Faye	> 0.5.0, < 1.0.4
Faye Project	Faye	>= 1.1.0, < 1.1.3
Faye Project	Faye	>= 1.2.0, < 1.2.5

References

https://github.com/faye/faye/commit/65d297d341b607f3cb0b5fa6021a625a991cc30ePatch, Third Party Advisory
https://github.com/faye/faye/security/advisories/GHSA-qpg4-4w7w-2mq5Exploit, Mitigation, Third Party Advisory
https://github.com/faye/faye/commit/65d297d341b607f3cb0b5fa6021a625a991cc30ePatch, Third Party Advisory
https://github.com/faye/faye/security/advisories/GHSA-qpg4-4w7w-2mq5Exploit, Mitigation, Third Party Advisory

Timeline

Published: Apr 29, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-11020?

How severe is CVE-2020-11020?

CVE-2020-11020 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.50% probability of exploitation in the next 30 days.

How do I fix CVE-2020-11020?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-11020?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST