CVE-2026-34831 Rack: Content-Length mismatch in Rack::Files error responses

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Filesfail sets the Content-Length response header using Stringsize instead of Stringbytesize. When the response body contains multibyte UTF-8 characters, the declared Content-Length is smaller than the...

CVE-2026-26961

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser extracts the boundary parameter from multipart/form-data using a greedy regular expression. When a Content-Type header contains multiple boundary parameters, Rack selects the last one...

CVE-2026-26961 Rack: Multipart Boundary Parsing Ambiguity allowing WAF Bypass

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser extracts the boundary parameter from multipart/form-data using a greedy regular expression. When a Content-Type header contains multiple boundary parameters, Rack selects the last one...

CVE-2026-26961

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser extracts the boundary parameter from multipart/form-data using a greedy regular expression. When a Content-Type header contains multiple boundary parameters, Rack selects the last one...

CVE-2026-26961 Rack: Multipart Boundary Parsing Ambiguity allowing WAF Bypass

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser extracts the boundary parameter from multipart/form-data using a greedy regular expression. When a Content-Type header contains multiple boundary parameters, Rack selects the last one...

CVE-2026-26961 Rack: Multipart Boundary Parsing Ambiguity allowing WAF Bypass

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser extracts the boundary parameter from multipart/form-data using a greedy regular expression. When a Content-Type header contains multiple boundary parameters, Rack selects the last one...

CVE-2026-26961

Rack vulnerable component: Rack::Multipart::Parser extracts multipart boundary from Content-Type using a greedy regex, causing last-boundary selection when multiple boundaries exist. This can allow smuggling of multipart content past upstream validation. Affected versions are before 2.2.23, 3.1.2...

CVE-2026-34230

Rack is a modular Ruby web server interface. CVE-2026-34230 describes a denial-of-service risk where Rack::Utils.select_best_encoding enters quadratic time on Accept-Encoding headers with many wildcard entries, enabling an unauthenticated attacker to exhaust CPU in the Rack::Deflater path. The is...

CVE-2026-34230 Rack: Quadratic complexity in Rack::Utils.select_best_encoding via wildcard Accept-Encoding header

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.selectbestencoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard entries. Because this method is used by Rack::Deflater to choose a respon...

CVE-2026-34230 Rack: Quadratic complexity in Rack::Utils.select_best_encoding via wildcard Accept-Encoding header

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.selectbestencoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard entries. Because this method is used by Rack::Deflater to choose a respon...

CVE-2026-34230

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.selectbestencoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard entries. Because this method is used by Rack::Deflater to choose a respon...

CVE-2026-34230 Rack: Quadratic complexity in Rack::Utils.select_best_encoding via wildcard Accept-Encoding header

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.selectbestencoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard entries. Because this method is used by Rack::Deflater to choose a respon...

CVE-2026-34230

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Utils.selectbestencoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard entries. Because this method is used by Rack::Deflater to choose a respon...

PT-2026-29923

Summary Rack::Multipart::Parser unfolds folded multipart part headers incorrectly. When a multipart header contains an obs-fold sequence, Rack preserves the embedded CRLF in parsed parameter values such as filename or name instead of removing the folded line break during unfolding. As a result,...

Rack 安全漏洞

Rack is a modular Ruby web server interface developed by Rack authors. Vulnerabilities exist in versions of Rack prior to 2.2.23, 3.1.21, and 3.2.6. These vulnerabilities stem from the use of Stringsize instead of Stringbytesize to set the Content-Length response header in Rack::Filesfail, which...

PT-2026-29812

Name of the Vulnerable Software and Affected Versions Rack versions prior to 2.2.23, 3.1.21, and 3.2.6 Description Rack::Static uses a simple string prefix check to determine if a request should be served as a static file. When configured with URL prefixes like "/css", it matches any request path...

PT-2026-29815

Name of the Vulnerable Software and Affected Versions Rack versions prior to 2.2.23, 3.1.21, and 3.2.6 Description The Rack::Utils.get byte ranges function parses the HTTP Range header without limiting the number of individual byte ranges. While a previous fix for CVE-2024-26141 prevents ranges...

Rack 安全漏洞

Rack is a modular Ruby web server interface developed by Rack authors. Vulnerabilities exist in versions of Rack prior to 2.2.23, 3.1.21, and 3.2.6. These vulnerabilities stem from Rack::Utils.selectbestencoding, which has a quadratic time complexity when processing Accept-Encoding headers...

Rack 安全漏洞

Rack is a modular Ruby web server interface developed by Rack authors. Vulnerabilities exist in versions of Rack prior to 2.2.23, 3.1.21, and 3.2.6. These vulnerabilities stem from Rack::Utils.getbyteranges, which does not limit the number of individual byte ranges when parsing HTTP Range headers...

PT-2026-29809

Name of the Vulnerable Software and Affected Versions Rack versions prior to 2.2.23, 3.1.21, and 3.2.6 Description Rack::Utils.select best encoding processes Accept-Encoding values with quadratic time complexity when the header contains many wildcard entries. Because this method is used by...