How severe is CVE-2020-11020?

CVE-2020-11020 has a CVSS 3.x base score of 8.5, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2020-11020 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11020?

CVE-2020-11020 primarily affects Faye Project Faye. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-11020?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-11020 published?

CVE-2020-11020 was published on 2020-04-29 and last updated on 2026-06-17.

CVE-2020-11020

CVE-2020-11020 is a high-severity vulnerability in Faye Project Faye with a CVSS 3.x base score of 8.5. 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-287.

Key facts

Severity: High (CVSS 3.x base score 8.5)
CVSS v2: 7.5
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Faye Project Faye
Published: 2020-04-29
Last modified: 2026-06-17

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.

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.
How severe is CVE-2020-11020?: CVE-2020-11020 has a CVSS 3.x base score of 8.5, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2020-11020 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11020?: CVE-2020-11020 primarily affects Faye Project Faye. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-11020?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-11020 published?: CVE-2020-11020 was published on 2020-04-29 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:faye_project:faye:*:*:*:*:*:node.js:*:*
cpe:2.3:a:faye_project:faye:*:*:*:*:*:ruby:*:*

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