How severe is CVE-2009-2422?

CVE-2009-2422 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2009-2422 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-2422?

CVE-2009-2422 primarily affects Rubyonrails Ruby On Rails. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2009-2422?

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-2009-2422 published?

CVE-2009-2422 was published on 2009-07-10 and last updated on 2026-06-16.

CVE-2009-2422

CVE-2009-2422 is a critical-severity vulnerability in Rubyonrails Ruby On Rails with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Rubyonrails Ruby On Rails
Published: 2009-07-10
Last modified: 2026-06-16

Description

The example code for the digest authentication functionality (http_authentication.rb) in Ruby on Rails before 2.3.3 defines an authenticate_or_request_with_http_digest block that returns nil instead of false when the user does not exist, which allows context-dependent attackers to bypass authentication for applications that are derived from this example by sending an invalid username without a password.

Frequently asked questions

What is CVE-2009-2422?: The example code for the digest authentication functionality (http_authentication.rb) in Ruby on Rails before 2.3.3 defines an authenticate_or_request_with_http_digest block that returns nil instead of false when the user does not exist, which allows context-dependent attackers to bypass authentication for applications that are derived from this example by sending an invalid username without a password.
How severe is CVE-2009-2422?: CVE-2009-2422 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2009-2422 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-2422?: CVE-2009-2422 primarily affects Rubyonrails Ruby On Rails. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2009-2422?: 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-2009-2422 published?: CVE-2009-2422 was published on 2009-07-10 and last updated on 2026-06-16.

References

Affected products (5)

cpe:2.3:a:rubyonrails:ruby_on_rails:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.5.8:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x_server:10.5.8:*:*:*:*:*:*:*

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