How severe is CVE-2021-22942?

CVE-2021-22942 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-22942 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22942?

CVE-2021-22942 affects Rubyonrails Rails. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-22942?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-22942 published?

CVE-2021-22942 was published on 2021-10-18 and last updated on 2026-06-17.

CVE-2021-22942

CVE-2021-22942 is a medium-severity vulnerability in Rubyonrails Rails with a CVSS 3.x base score of 6.1. 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-601.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 5.8
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Rubyonrails Rails
Published: 2021-10-18
Last modified: 2026-06-17

Description

A possible open redirect vulnerability in the Host Authorization middleware in Action Pack >= 6.0.0 that could allow attackers to redirect users to a malicious website.

Frequently asked questions

What is CVE-2021-22942?: A possible open redirect vulnerability in the Host Authorization middleware in Action Pack >= 6.0.0 that could allow attackers to redirect users to a malicious website.
How severe is CVE-2021-22942?: CVE-2021-22942 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-22942 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22942?: CVE-2021-22942 affects Rubyonrails Rails. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-22942?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-22942 published?: CVE-2021-22942 was published on 2021-10-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*

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