Vulnerability Database

393,392

Total vulnerabilities in the database

CVE-2013-4073 — ruby-lang / ruby

Cryptographic Issues

The OpenSSL::SSL.verify_certificate_identity function in lib/openssl/ssl.rb in Ruby 1.8 before 1.8.7-p374, 1.9 before 1.9.3-p448, and 2.0 before 2.0.0-p247 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

  • Published: Aug 18, 2013
  • Updated: Oct 3, 2026
  • CVE: CVE-2013-4073
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v2:

  • Severity: Medium
  • Score: 6.8
  • AV:N/AC:M/Au:N/C:P/I:P/A:P

CWEs:

Software Affected versions
ruby-lang / ruby = 1.8.6-26
ruby-lang / ruby = 1.8.7
ruby-lang / ruby = 1.8.7-p160
ruby-lang / ruby = 1.8.7-p17
ruby-lang / ruby = 1.8.7-p173
ruby-lang / ruby = 1.8.7-p174
ruby-lang / ruby = 1.8.7-p22
ruby-lang / ruby = 1.8.7-p248
ruby-lang / ruby = 1.8.7-p249
ruby-lang / ruby = 1.8.7-p299
ruby-lang / ruby = 1.8.7-p301
ruby-lang / ruby = 1.8.7-p302
ruby-lang / ruby = 1.8.7-p330
ruby-lang / ruby = 1.8.7-p334
ruby-lang / ruby = 1.8.7-p352
ruby-lang / ruby = 1.8.7-p357
ruby-lang / ruby = 1.8.7-p358
ruby-lang / ruby = 1.8.7-p370
ruby-lang / ruby = 1.8.7-p371
ruby-lang / ruby = 1.8.7-p373
ruby-lang / ruby = 1.8.7-p71
ruby-lang / ruby = 1.8.7-p72
ruby-lang / ruby = 1.8.7-preview1
ruby-lang / ruby = 1.8.7-preview2
ruby-lang / ruby = 1.8.7-preview3
ruby-lang / ruby = 1.8.7-preview4
ruby-lang / ruby = 1.9.3
ruby-lang / ruby = 1.9.3-p0
ruby-lang / ruby = 1.9.3-p125
ruby-lang / ruby = 1.9.3-p194
ruby-lang / ruby = 1.9.3-p286
ruby-lang / ruby = 1.9.3-p383
ruby-lang / ruby = 1.9.3-p385
ruby-lang / ruby = 1.9.3-p392
ruby-lang / ruby = 1.9.3-p426
ruby-lang / ruby = 1.9.3-p429
ruby-lang / ruby = 2.0.0-p0
ruby-lang / ruby = 2.0.0-p195
ruby-lang / ruby = 2.0.0-preview1
ruby-lang / ruby = 2.0.0-preview2
ruby-lang / ruby = 2.0.0-rc1
ruby-lang / ruby = 2.0.0-rc2

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.