Ruby
CVE-2020-25613
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V4 - API and Web Service HTTP request consistency
|
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could manipulate HTTP request interpretation between frontend and backend servers by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
An issue was discovered in Ruby through 2.5.8, 2.6.x through 2.6.6, and 2.7.x through 2.7.1. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This HTTP Request/Response Smuggling vulnerability could allow attackers to manipulate HTTP request interpretation between frontend and backend servers.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Enforce strict HTTP parsing, normalize requests at proxy layer, use HTTP/2 end-to-end, reject ambiguous headers.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in rubygems
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Technical ContextAI · show details
This vulnerability is classified as HTTP Request/Response Smuggling (CWE-444), which allows attackers to manipulate HTTP request interpretation between frontend and backend servers. An issue was discovered in Ruby through 2.5.8, 2.6.x through 2.6.6, and 2.7.x through 2.7.1. WEBrick, a simple HTTP server bundled with Ruby, had not checked the transfer-encoding header value rigorously. An attacker may potentially exploit this issue to bypass a reverse proxy (which also has a poor header check), which may lead to an HTTP Request Smuggling attack. Affected products include: Ruby-Lang Ruby, Ruby-Lang Webrick, Fedoraproject Fedora. Version information: through 2.5.8.
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
An issue was discovered in Ruby through 2.5.8, 2.6.x through 2.6.6, and 2.7.x through 2.7.1. WEBrick, a simple HTTP server bundled with Ruby, had not checked the transfer-encoding header value rigorously. An attacker may potentially exploit this issue to bypass a reverse proxy (which also has a poor header check), which may lead to an HTTP Request Smuggling attack.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
HTTP request smuggling exploits inconsistencies in how front-end and back-end servers parse HTTP message boundaries.
Affected Products (CPE)NVD
Ruby before 2.4.3 allows Net::FTP command injection. Rated high severity (CVSS 8.8), this vulnerability is remotely expl
The lazy_initialize function in lib/resolv.rb in Ruby through 2.4.3 uses Kernel#open, which might allow Command Injectio
Ruby through 2.2.7, 2.3.x through 2.3.4, and 2.4.x through 2.4.1 can expose arbitrary memory during a JSON.generate call
Type confusion exists in two methods of Ruby's WIN32OLE class, ole_invoke and ole_query_interface. Rated critical severi
Authenticated remote code execution in OpenC3 COSMOS (Ruby gem 'openc3' versions 5.1.0 through 7.2.1) lets any logged-in
Type confusion exists in _cancel_eval Ruby's TclTkIp class method. Rated critical severity (CVSS 9.8), this vulnerabilit
An exploitable heap overflow vulnerability exists in the Fiddle::Function.new "initialize" function functionality of Rub
An issue was discovered in Oniguruma 6.2.0, as used in Oniguruma-mod in Ruby through 2.4.1 and mbstring in PHP through 7
Stored XSS in Bugsink error tracking tool before 2.0.13 allows unauthenticated attackers to inject persistent scripts th
Ruby before 2.4.2, 2.3.5, and 2.2.8 is vulnerable to a malicious format string which contains a precious specifier (*) w
Heap-based buffer overflow in Ruby 1.8, 1.9 before 1.9.3-p484, 2.0 before 2.0.0-p353, 2.1 before 2.1.0 preview2, and tru
Heap-use-after-free in the Ruby json gem's native C extension (versions 2.20.0 through 2.21.1) allows an unauthenticated
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