Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2009-0642

22
FAUCET Score

CVE-2009-0642 describes a vulnerability in Ruby versions 1.8 and 1.9, specifically within the ext/openssl/ossl_ocsp.c component. This flaw stems from an insufficient check of the OCSP_basic_verify function's return value, potentially allowing remote attackers to present and validate invalid X.509 certificates, including revoked ones. With a CVSS score of 6.8, this vulnerability is of medium severity, requiring medium attack complexity and potentially leading to partial compromise of confidentiality, integrity, and availability. There is no evidence of active exploitation, public exploit code, or significant community discussion for this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
1.8CPE matchmatch criteria
cpe:2.3:a:ruby-lang:ruby:1.8:*:*:*:*:*:*:*
1.9CPE matchmatch criteria
cpe:2.3:a:ruby-lang:ruby:1.9:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 2.0

6.8MEDIUM

AV:N/AC:M/Au:N/C:P/I:P/A:P

Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Exploitability Score
8.6
Impact Score
6.4
CvssVersion
2.0

Exploit Intelligence

EPSS Score
2.64%
Probability of exploitation in next 30 days
EPSS Percentile
84.0%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0264 is in the 75th percentile among its peer group of 19,958 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.2 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 4Fixed in: ruby-0:1.8.1-7.el4_8.3
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 5Fixed in: ruby-0:1.8.5-5.el5_3.7
View patch

Vendor Advisories (1)

redhatCVE-2009-0642Moderate

ruby: Incorrect checks for validity of X.509 certificates

Jan 29, 2009

References

bugs.debian.org / cgi-bin/bugreport.cgi
redmine.ruby-lang.org / issues/show/1091
Exploit
secunia.com / advisories/33750
secunia.com / advisories/35699
secunia.com / advisories/35937
exchange.xforce.ibmcloud.com / vulnerabilities/48761
oval.cisecurity.org / repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11450
mandriva.com / security/advisories
redhat.com / support/errata/RHSA-2009-1140.html
securityfocus.com / bid/33769
securitytracker.com / id
ubuntu.com / usn/USN-805-1