{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/echo-v3/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":7.5,"id":"CVE-2026-55677"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Echo (v5)","Echo (v4)","Echo (v3)"],"_cs_severities":["high"],"_cs_tags":[],"_cs_type":"advisory","_cs_vendors":["Labstack"],"content_html":"\u003cp\u003eThe Echo web framework, versions of v5 prior to 5.2.0, v4 prior to 4.15.3, and legacy v3 up to 3.3.10, is affected by a path normalization vulnerability (CVE-2026-55677). The issue stems from a disagreement between the routing engine and the StaticDirectoryHandler regarding URL decoding. Specifically, the router matches requests using the raw encoded URL path (keeping '%2F' as is), while the static file handler decodes '%2F' into a literal '/' during filesystem resolution.\u003c/p\u003e\n\u003cp\u003eThis discrepancy allows an attacker to craft requests that bypass route-level access control middleware by obfuscating protected path segments. If an application protects a sensitive directory (e.g., /admin) with authentication middleware, an attacker can use an encoded slash to request paths like '/admin%2Fconfig.json'. The router fails to match the '/admin' pattern, skipping the authentication check, while the static handler later decodes the string to '/admin/config.json', resulting in unauthorized file disclosure.\u003c/p\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation allows unauthorized disclosure of static files from the application's file system. Applications that serve static files and implement route-based access control are at risk of data leakage. The number of affected deployments is high, given Echo's widespread usage in Go web applications.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade to Echo v5.2.0, v4.15.3, or later versions immediately to address CVE-2026-55677.\u003c/li\u003e\n\u003cli\u003eReview applications using \u003ccode\u003eStaticFS\u003c/code\u003e or \u003ccode\u003eStaticDirectoryHandler\u003c/code\u003e to ensure that route-level middleware is not bypassed by client-side URL encoding.\u003c/li\u003e\n\u003cli\u003eAudit web server and application logs for URLs containing encoded characters, specifically '%2F', which may indicate attempted exploitation.\u003c/li\u003e\n\u003cli\u003eEnsure security configuration for static file routes does not rely solely on path-prefix authentication if the underlying framework router handles path normalization inconsistently.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-08-25T18:50:45Z","date_published":"2026-08-25T18:50:45Z","id":"https://feed.craftedsignal.io/briefs/2026-08-echo-path-traversal/","summary":"An inconsistency between URL path decoding in the Echo framework router and static file handler allows attackers to bypass authentication by using encoded slashes.","title":"Path Normalization Vulnerability in Echo Web Framework","url":"https://feed.craftedsignal.io/briefs/2026-08-echo-path-traversal/"}],"language":"en","title":"CraftedSignal Threat Feed - Echo (V3)","version":"https://jsonfeed.org/version/1.1"}