CVE-2009-2422

Name: CVE-2009-2422
Creator: NVD / NIST
Published: 2009-07-10T15:30:00.25+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 3.38%

Last modified Jun 16, 2026

CVE-2009-2422 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 3.38% chance of exploitation in the next 30 days.

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.

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

3.38%

87.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-287

Affected Software

Vendor	Product	Versions
Rubyonrails	Ruby On Rails	< 2.3.3
Apple	Mac Os X	>= 10.6.0, < 10.6.3
Apple	Mac Os X	10.5.8
Apple	Mac Os X Server	>= 10.6.0, < 10.6.3
Apple	Mac Os X Server	10.5.8

References

http://lists.apple.com/archives/security-announce/2010//Mar/msg00001.htmlMailing List
http://n8.tumblr.com/post/117477059/security-hole-found-in-rails-2-3sExploit, Patch
http://secunia.com/advisories/35702Broken Link, Vendor Advisory
http://support.apple.com/kb/HT4077Third Party Advisory
http://weblog.rubyonrails.org/2009/6/3/security-problem-with-authenticate_with_http_digestPatch
http://www.securityfocus.com/bid/35579Broken Link, Patch, Third Party Advisory, VDB Entry
http://www.vupen.com/english/advisories/2009/1802Broken Link, Patch, Vendor Advisory
https://exchange.xforce.ibmcloud.com/vulnerabilities/51528Third Party Advisory, VDB Entry
http://lists.apple.com/archives/security-announce/2010//Mar/msg00001.htmlMailing List
http://n8.tumblr.com/post/117477059/security-hole-found-in-rails-2-3sExploit, Patch
http://secunia.com/advisories/35702Broken Link, Vendor Advisory
http://support.apple.com/kb/HT4077Third Party Advisory
http://weblog.rubyonrails.org/2009/6/3/security-problem-with-authenticate_with_http_digestPatch
http://www.securityfocus.com/bid/35579Broken Link, Patch, Third Party Advisory, VDB Entry
http://www.vupen.com/english/advisories/2009/1802Broken Link, Patch, Vendor Advisory
https://exchange.xforce.ibmcloud.com/vulnerabilities/51528Third Party Advisory, VDB Entry

Timeline

Published: Jul 10, 2009
Last Modified: Jun 16, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2009-2422?

How severe is CVE-2009-2422?

CVE-2009-2422 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 3.38% probability of exploitation in the next 30 days.

How do I fix CVE-2009-2422?

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-2009-2422?

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

Scan your code now

Source: NVD / NIST