Ruby-lang vulnerabilities
We track 12 vulnerabilities in Ruby-lang products across 5 products. 12 are rated high or critical, and 1 has been exploited in real attacks. The most recent was published on October 13, 2026.
Latest Ruby-lang vulnerabilities
- 10.0 Critical severity
GitLab Community Edition and Enterprise Edition Integer Overflow or Wraparound Exploited
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 19.2 before 19.2.8, 19.3 before 19.3.5, and 19.4 before 19.4.2 that, under certain conditions, could have allowed an unauthenticated user to execute arbitrary code on the GitLab server
- 8.1 High severity
Ruby: Concurrent Execution using Shared Resource with Improper Synchronization
An issue was discovered in Ruby 4 before 4.0.5. A race condition leading to a use-after-free in the pthread-based getaddrinfo timeout handler (rb_getaddrinfo in ext/socket/raddrinfo.c) allows a remote attacker who can delay DNS responses near the user-specifie
- 9.8 Critical severity
net-imap: Improper Neutralization of Special Elements used in a Command
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this s
- 7.4 High severity
net-imap: Missing Report of Error Condition
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue
- 7.5 High severity
net-imap: Inefficient Algorithmic Complexity
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, Net::IMAP::ResponseReader has quadratic time complexity when reading large responses containing many string literals. A host
- 7.5 High severity
json: Out-of-bounds Read
JSON is a JSON implementation for Ruby. Starting in version 2.10.0 and prior to version 2.10.2, a specially crafted document could cause an out of bound read, most likely resulting in a crash. Versions prior to 2.10.0 are not vulnerable. Version 2.10.2 fixes t
- 7.5 High severity
CGI: Allocation of Resources Without Limits or Throttling
In the CGI gem before 0.4.2 for Ruby, the CGI::Cookie.parse method in the CGI library contains a potential Denial of Service (DoS) vulnerability. The method does not impose any limit on the length of the raw cookie value it processes. This oversight can lead t
- 7.5 High severity
rexml: Uncontrolled Resource Consumption
REXML is an XML toolkit for Ruby. The REXML gem 3.3.2 has a DoS vulnerability when it parses an XML that has many entity expansions with SAX2 or pull parser API. The REXML gem 3.3.3 or later include the patch to fix the vulnerability.
- 7.5 High severity
rexml: Uncontrolled Resource Consumption
REXML is an XML toolkit for Ruby. The REXML gem before 3.3.2 has some DoS vulnerabilities when it parses an XML that has many specific characters such as whitespace character, `>]` and `]>`. The REXML gem 3.3.3 or later include the patches to fix these vulnera
- 9.8 Critical severity
ruby: Buffer Copy without Checking Size of Input
A buffer-overread issue was discovered in StringIO 3.0.1, as distributed in Ruby 3.0.x through 3.0.6 and 3.1.x through 3.1.4. The ungetbyte and ungetc methods on a StringIO can read past the end of a string, and a subsequent call to StringIO.gets may return th
- 7.5 High severity
Ruby: Out-of-bounds Read
There is a buffer over-read in Ruby before 2.6.10, 2.7.x before 2.7.6, 3.x before 3.0.4, and 3.1.x before 3.1.2. It occurs in String-to-Float conversion, including Kernel#Float and String#to_f.
- 9.8 Critical severity
Ruby: Double Free
A double free was found in the Regexp compiler in Ruby 3.x before 3.0.4 and 3.1.x before 3.1.2. If a victim attempts to create a Regexp from untrusted user input, an attacker may be able to write to unexpected memory locations.