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.
CVSS Details
- CVSS 3.1 Base Score: 5.9
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N)
- CVSS 3.0 Base Score: 6.5
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | amazon-linux-ami-2-upgrade-rubyamazon-linux-ami-2-upgrade-ruby-debuginfoamazon-linux-ami-2-upgrade-ruby-develamazon-linux-ami-2-upgrade-ruby-docamazon-linux-ami-2-upgrade-ruby-irbamazon-linux-ami-2-upgrade-ruby-libsamazon-linux-ami-2-upgrade-ruby-tcltkamazon-linux-ami-2-upgrade-rubygem-bigdecimalamazon-linux-ami-2-upgrade-rubygem-io-consoleamazon-linux-ami-2-upgrade-rubygem-jsonamazon-linux-ami-2-upgrade-rubygem-minitestamazon-linux-ami-2-upgrade-rubygem-psychamazon-linux-ami-2-upgrade-rubygem-rakeamazon-linux-ami-2-upgrade-rubygem-rdocamazon-linux-ami-2-upgrade-rubygemsamazon-linux-ami-2-upgrade-rubygems-devel | May 20, 2026 | May 20, 2026 | |
| Amazon_linux_2023 | amazon-linux-2023-upgrade-ruby3-2amazon-linux-2023-upgrade-ruby3-2-bundled-gemsamazon-linux-2023-upgrade-ruby3-2-bundled-gems-debuginfoamazon-linux-2023-upgrade-ruby3-2-debuginfoamazon-linux-2023-upgrade-ruby3-2-debugsourceamazon-linux-2023-upgrade-ruby3-2-default-gemsamazon-linux-2023-upgrade-ruby3-2-develamazon-linux-2023-upgrade-ruby3-2-docamazon-linux-2023-upgrade-ruby3-2-libsamazon-linux-2023-upgrade-ruby3-2-libs-debuginfoamazon-linux-2023-upgrade-ruby3-2-rubygem-bigdecimalamazon-linux-2023-upgrade-ruby3-2-rubygem-bigdecimal-debuginfoamazon-linux-2023-upgrade-ruby3-2-rubygem-bundleramazon-linux-2023-upgrade-ruby3-2-rubygem-io-consoleamazon-linux-2023-upgrade-ruby3-2-rubygem-io-console-debuginfoamazon-linux-2023-upgrade-ruby3-2-rubygem-irbamazon-linux-2023-upgrade-ruby3-2-rubygem-jsonamazon-linux-2023-upgrade-ruby3-2-rubygem-json-debuginfoamazon-linux-2023-upgrade-ruby3-2-rubygem-minitestamazon-linux-2023-upgrade-ruby3-2-rubygem-power-assertamazon-linux-2023-upgrade-ruby3-2-rubygem-psychamazon-linux-2023-upgrade-ruby3-2-rubygem-psych-debuginfoamazon-linux-2023-upgrade-ruby3-2-rubygem-rakeamazon-linux-2023-upgrade-ruby3-2-rubygem-rbsamazon-linux-2023-upgrade-ruby3-2-rubygem-rbs-debuginfoamazon-linux-2023-upgrade-ruby3-2-rubygem-rdocamazon-linux-2023-upgrade-ruby3-2-rubygem-rexmlamazon-linux-2023-upgrade-ruby3-2-rubygem-rssamazon-linux-2023-upgrade-ruby3-2-rubygemsamazon-linux-2023-upgrade-ruby3-2-rubygems-develamazon-linux-2023-upgrade-ruby3-2-rubygem-test-unitamazon-linux-2023-upgrade-ruby3-2-rubygem-typeprof | Jul 30, 2025 | Jun 25, 2025 | |
| Apple Osx Ruby | apple-osx-upgrade-latest | Nov 4, 2025 | Nov 4, 2025 | |
| Debian | no-fix-debian-deb-package | Jun 27, 2025 | Jun 25, 2025 | |
| Huawei Euleros 2_0_sp10 | huawei-euleros-2_0_sp10-upgrade-rubyhuawei-euleros-2_0_sp10-upgrade-ruby-helphuawei-euleros-2_0_sp10-upgrade-ruby-irbhuawei-euleros-2_0_sp10-upgrade-rubygem-bigdecimalhuawei-euleros-2_0_sp10-upgrade-rubygem-did_you_meanhuawei-euleros-2_0_sp10-upgrade-rubygem-io-consolehuawei-euleros-2_0_sp10-upgrade-rubygem-jsonhuawei-euleros-2_0_sp10-upgrade-rubygem-opensslhuawei-euleros-2_0_sp10-upgrade-rubygem-psychhuawei-euleros-2_0_sp10-upgrade-rubygem-rdochuawei-euleros-2_0_sp10-upgrade-rubygems | Nov 12, 2025 | Nov 6, 2025 | |
| Redhat_linux | — | no-fix-redhat-rpm-package | Jul 9, 2025 | Jun 25, 2025 |
| Suse | — | suse-upgrade-libruby2_5-2_5suse-upgrade-ruby2-5suse-upgrade-ruby2-5-develsuse-upgrade-ruby2-5-devel-extrasuse-upgrade-ruby2-5-docsuse-upgrade-ruby2-5-doc-risuse-upgrade-ruby2-5-stdlib | Aug 14, 2025 | Aug 8, 2025 |
| Ubuntu | ubuntu-pro-upgrade-libruby2-3ubuntu-pro-upgrade-libruby2-5ubuntu-pro-upgrade-libruby2-7ubuntu-pro-upgrade-ruby2-3ubuntu-pro-upgrade-ruby2-5ubuntu-upgrade-ruby-webrick | Aug 4, 2025 | Jun 25, 2025 | |
| Vmware Photon_os | vmware-photon_os_update_tdnf | Sep 11, 2025 | Jun 25, 2025 |
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