Vulnerability in websocket-driver (CVE-2026-61666)
Summary
Vulnerability in websocket-driver (CVE-2026-61666). Risk of unauthorized operations or information disclosure. Exploitable via Host. Mitigation: upgrade to 0.8.2 or later.
Original description
The description as published by the source.
Impact
If this library is used to implement a WebSocket server on top of a TCP server, by using the WebSocket::Driver.server() method, then a client can cause the server to crash by sending a Host header that is not a valid host[:port] string. When this happens, a URI::InvalidURIError exception is raised which is not caught, and this can cause the server process to crash if the application does not catch the error from the parse() method itself.
Patches
The issue has been patched in version 0.8.2 by making the request parser catch URI::InvalidURIError and enter an error state if the Host header is malformed. This means the request is considered invalid and should not establish a WebSocket connection.
Workarounds
No known workarounds exist.
Acknowledgements
This issue was discovered and reported by Pranjali Thakur, DepthFirst Security Research Team.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-61666 has been found in websocket-driver.
Attackers can target a specific entry point like Host over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade websocket-driver to 0.8.2 or later.
If unsure, ask your IT team or search "websocket-driver CVE-2026-61666" on the vendor's site.
CVE-2026-61666 (websocket-driver) — CWE-248
Attack surface: Host
Patched: 0.8.2 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-248) exists in websocket-driver. Attackers reach the vulnerable code path via Host.
Check the vendor advisory for the affected versions of websocket-driver. Attack surface: Host.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 0.8.2.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'websocket-driver' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'websocket-driver' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
websocket-driverを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade websocket-driver to 0.8.2ステージング環境で 0.8.2 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-61666 ruby-websocket-driver
- Ubuntu UBUNTU-CVE-2026-61666 ruby-websocket-driver