Ruby WEBrick read_header HTTP Request Smuggling Vulnerability. This vulnerability allows remote attackers to smuggle arbitrary HTTP requests on affected installations of Ruby WEBrick. This issue is exploitable when the product is deployed behind an HTTP proxy that fulfills specific conditions.
The specific flaw exists within the read_headers method. The issue results from the inconsistent parsing of terminators of HTTP headers. An attacker can leverage this vulnerability to smuggle arbitrary HTTP requests. Was ZDI-CAN-21876.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | — | Upgrade rubygem-minitestUpgrade ruby-develUpgrade rubygems-develUpgrade rubygem-rakeUpgrade ruby-irbUpgrade ruby-debuginfoUpgrade rubygem-rdocUpgrade rubyUpgrade rubygem-io-consoleUpgrade ruby-docUpgrade rubygem-psychUpgrade ruby-libsUpgrade rubygem-bigdecimalUpgrade rubygem-jsonUpgrade ruby-tcltkUpgrade rubygems | May 20, 2026 | May 20, 2026 |
| Amazon_linux_2023 | — | Upgrade ruby3.2-rubygem-psychUpgrade ruby3.2-rubygem-rakeUpgrade ruby3.2-rubygem-bundlerUpgrade ruby3.2-bundled-gems-debuginfoUpgrade ruby3.2-rubygem-json-debuginfoUpgrade ruby3.2-rubygem-rexmlUpgrade ruby3.2-rubygem-io-consoleUpgrade ruby3.2-rubygem-irbUpgrade ruby3.2-rubygems-develUpgrade ruby3.2-rubygem-test-unitUpgrade ruby3.2-develUpgrade ruby3.2-libs-debuginfoUpgrade ruby3.2-rubygem-jsonUpgrade ruby3.2-rubygem-rbsUpgrade ruby3.2Upgrade ruby3.2-rubygem-minitestUpgrade ruby3.2-rubygem-rbs-debuginfoUpgrade ruby3.2-rubygem-rdocUpgrade ruby3.2-rubygem-bigdecimal-debuginfoUpgrade ruby3.2-rubygem-bigdecimalUpgrade ruby3.2-debuginfoUpgrade ruby3.2-rubygem-rssUpgrade ruby3.2-rubygem-typeprofUpgrade ruby3.2-debugsourceUpgrade ruby3.2-libsUpgrade ruby3.2-default-gemsUpgrade ruby3.2-docUpgrade ruby3.2-rubygem-power_assertUpgrade ruby3.2-rubygem-io-console-debuginfoUpgrade ruby3.2-bundled-gemsUpgrade ruby3.2-rubygemsUpgrade ruby3.2-rubygem-psych-debuginfo | Jul 30, 2025 | Jun 25, 2025 |
| Apple Osx Ruby | — | Upgrade macOS to the latest version | Nov 4, 2025 | Nov 3, 2025 |
| Debian | — | Upgrade ruby-webrick | Jun 27, 2025 | Jun 25, 2025 |
| Huawei Euleros 2_0_sp10 | — | Upgrade ruby-irbUpgrade rubygem-bigdecimalUpgrade rubygem-rdocUpgrade rubygem-jsonUpgrade rubygem-psychUpgrade rubygemsUpgrade rubygem-opensslUpgrade rubyUpgrade ruby-helpUpgrade rubygem-io-consoleUpgrade rubygem-did_you_mean | Nov 12, 2025 | Nov 6, 2025 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Jun 25, 2025 |
| Suse | — | Upgrade ruby2.5-develUpgrade ruby2.5-docUpgrade ruby2.5-doc-riUpgrade libruby2_5-2_5Upgrade ruby2.5-stdlibUpgrade ruby2.5Upgrade ruby2.5-devel-extra | Aug 14, 2025 | Aug 8, 2025 |
| Ubuntu | — | Upgrade libruby2.7 (Ubuntu Pro)Upgrade ruby2.3 (Ubuntu Pro)Upgrade ruby2.5 (Ubuntu Pro)Upgrade ruby-webrickUpgrade libruby2.5 (Ubuntu Pro)Upgrade libruby2.3 (Ubuntu Pro) | Aug 4, 2025 | Jun 25, 2025 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Sep 11, 2025 | Jun 25, 2025 |
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