Rack vulnerabilities
We track 25 vulnerabilities in Rack products across 3 products. 25 are rated high or critical, and none are known to be exploited. The most recent was published on November 9, 2026.
Latest Rack vulnerabilities
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Multipart::Parser can retain parsed data in its internal StringScanner buffer when reads end inside or immediately after multipart headers. An unauthenticated attacker can a
- 9.8 Critical severity
rack-session: Improper Authentication
Rack::Session is a session management implementation for Rack. From 2.0.0 to before 2.1.2, Rack::Session::Cookie incorrectly handles decryption failures when configured with secrets:. If cookie decryption fails, the implementation falls back to a default decod
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21, and 3.2.0 to before 3.2.6, Rack::Multipart::Parser#handle_mime_head parses quoted multipart parameters such as Content-Disposition: form-data; name="..." using repeated St
- 7.5 High severity
rack: Permissive Regular Expression
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Sendfile#map_accel_path interpolates the value of the X-Accel-Mapping request header directly into a regular expression when rewriting file paths for X-Accel-Redire
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser only wraps the request body in a BoundedIO when CONTENT_LENGTH is present. When a multipart/form-data request is sent without a Content-Length hea
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.get_byte_ranges parses the HTTP Range header without limiting the number of individual byte ranges. Although the existing fix for CVE-2024-26141 rejects range
- 7.5 High severity
rack: Partial String Comparison
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines whether a request should be served as a static file using a simple string prefix check. When configured with URL prefixes such as "/css", it match
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.select_best_encoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard (*) entries. Because this method i
- 7.5 High severity
rack: Improper Limitation of a Pathname to a Restricted Directory
Rack is a modular Ruby web server interface. Prior to versions 2.2.22, 3.1.20, and 3.2.5, `Rack::Directory`’s path check used a string prefix match on the expanded path. A request like `/../root_example/` can escape the configured root if the target path start
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to versions 2.2.20, 3.1.18, and 3.2.3, `Rack::Request#POST` reads the entire request body into memory for `Content-Type: application/x-www-form-urlencoded`, calling `rack.input.read(nil)` without enforcing a l
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. In versions prior to 2.2.19, 3.1.17, and 3.2.2, `Rack::Multipart::Parser` can accumulate unbounded data when a multipart part’s header block never terminates with the required blank line (`CRLFCRLF`). The parser kee
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. In versions prior to 2.2.19, 3.1.17, and 3.2.2, ``Rack::Multipart::Parser` stores non-file form fields (parts without a `filename`) entirely in memory as Ruby `String` objects. A single large text field in a multipa
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. In versions prior to 2.2.19, 3.1.17, and 3.2.2, `Rack::Multipart::Parser` buffers the entire multipart preamble (bytes before the first boundary) in memory without any size limit. A client can send a large preamble
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to version 2.2.18, Rack::QueryParser enforces its params_limit only for parameters separated by &, while still splitting on both & and ;. As a result, attackers could use ; separators to bypass the parameter c
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Prior to versions 2.2.14, 3.0.16, and 3.1.14, `Rack::QueryParser` parses query strings and `application/x-www-form-urlencoded` bodies into Ruby data structures without imposing any limit on the number of parameters,
- 7.5 High severity
rack: Relative Path Traversal
Rack provides an interface for developing web applications in Ruby. Prior to versions 2.2.13, 3.0.14, and 3.1.12, `Rack::Static` can serve files under the specified `root:` even if `urls:` are provided, which may expose other files under the specified `root:`
- 7.5 High severity
rack: Improper Neutralization of CRLF Sequences
Rack is a modular Ruby web server interface. The Rack::Sendfile middleware logs unsanitised header values from the X-Sendfile-Type header. An attacker can exploit this by injecting escape sequences (such as newline characters) into the header, resulting in log
- 8.6 High severity
rack-contrib: Allocation of Resources Without Limits or Throttling
rack-contrib provides contributed rack middleware and utilities for Rack, a Ruby web server interface. Versions of rack-contrib prior to 2.5.0 are vulnerable to denial of service due to the fact that the user controlled data `profiler_runs` was not constrained
- 7.5 High severity
rack: Inefficient Regular Expression Complexity
Rack is a modular Ruby web server interface. Carefully crafted headers can cause header parsing in Rack to take longer than expected resulting in a possible denial of service issue. Accept and Forwarded headers are impacted. Ruby 3.2 has mitigations for this p
- 7.5 High severity
rack: Uncontrolled Resource Consumption
Rack is a modular Ruby web server interface. Carefully crafted Range headers can cause a server to respond with an unexpectedly large response. Responding with such large responses could lead to a denial of service issue. Vulnerable applications will use the `
- 7.5 High severity
rack: Inefficient Regular Expression Complexity
Rack is a modular Ruby web server interface. Carefully crafted content type headers can cause Rack’s media type parser to take much longer than expected, leading to a possible denial of service vulnerability (ReDos 2nd degree polynomial). This vulnerability is
- 7.5 High severity
https://github.com/rack/rack: Allocation of Resources Without Limits or Throttling
A DoS vulnerability exists in Rack <v3.0.4.2, <v2.2.6.3, <v2.1.4.3 and <v2.0.9.3 within in the Multipart MIME parsing code in which could allow an attacker to craft requests that can be abuse to cause multipart parsing to take longer than expected.
- 7.5 High severity
https://github.com/rack/rack: Inefficient Regular Expression Complexity
A denial of service vulnerability in the multipart parsing component of Rack fixed in 2.0.9.2, 2.1.4.2, 2.2.4.1 and 3.0.0.1 could allow an attacker tocraft input that can cause RFC2183 multipart boundary parsing in Rack to take an unexpected amount of time, po
- 7.5 High severity
https://github.com/rack/rack: Inefficient Regular Expression Complexity
There is a denial of service vulnerability in the Content-Disposition parsingcomponent of Rack fixed in 2.0.9.2, 2.1.4.2, 2.2.4.1, 3.0.0.1. This could allow an attacker to craft an input that can cause Content-Disposition header parsing in Rackto take an unexp
- 7.5 High severity
https://github.com/rack/rack: Inefficient Regular Expression Complexity
A denial of service vulnerability in the Range header parsing component of Rack >= 1.5.0. A Carefully crafted input can cause the Range header parsing component in Rack to take an unexpected amount of time, possibly resulting in a denial of service attack vect