{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/vendors/ech0/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Ech0"],"_cs_severities":["high"],"_cs_tags":["ech0","privilege-escalation","data-exfiltration","access-token"],"_cs_type":"advisory","_cs_vendors":["Ech0"],"content_html":"\u003cp\u003eEch0, a web application, suffers from a vulnerability where scoped access tokens do not reliably enforce least privilege. Several privileged admin routes lack scope checks, and critically, the \u003ccode\u003e/api/backup/export\u003c/code\u003e handler strips token scope metadata. An attacker obtaining a limited-scope admin access token can bypass intended restrictions. This allows access to sensitive admin functionalities and data. The vulnerability was confirmed on Ech0 versions prior to 4.3.5. Successful exploitation enables an attacker to escalate privileges and potentially exfiltrate sensitive data, including database and log files. This circumvents intended access controls and poses a significant security risk.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker compromises or obtains a low-privilege Ech0 admin account, such as one with only \u003ccode\u003eecho:read\u003c/code\u003e scope.\u003c/li\u003e\n\u003cli\u003eThe attacker uses the compromised account to generate a new access token with limited scopes (e.g., \u003ccode\u003eecho:read\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a request to \u003ccode\u003e/api/inbox\u003c/code\u003e using the low-scope access token in the \u003ccode\u003eAuthorization\u003c/code\u003e header. Because this route lacks scope enforcement, the request succeeds despite the token's limited privileges.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a request to \u003ccode\u003e/api/backup/export?token=\u0026lt;low_scope_admin_token\u0026gt;\u003c/code\u003e using the low-scope access token as the token parameter.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003e/api/backup/export\u003c/code\u003e handler parses the token, extracts the user ID, and discards all other token metadata (scopes, audience, etc.).\u003c/li\u003e\n\u003cli\u003eThe handler then rebuilds a new user context based only on the user ID, effectively elevating the low-scope token to full admin privileges.\u003c/li\u003e\n\u003cli\u003eThe backup service executes, generating a ZIP archive containing sensitive data, including the application database and logs.\u003c/li\u003e\n\u003cli\u003eThe attacker downloads the backup archive, gaining access to potentially sensitive information.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation allows attackers with limited admin access to escalate their privileges and access sensitive functionalities in Ech0. This bypasses least-privilege access controls. The confirmed impact includes unauthorized access to the \u003ccode\u003e/api/inbox\u003c/code\u003e and complete backup exports. Attackers can exfiltrate ZIP archives containing application databases and logs. This can lead to the exposure of user credentials, configuration data, and other confidential information. This vulnerability impacts organizations relying on access tokens for privilege separation and increases the risk of data breaches.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply scope enforcement to all privileged routes in Ech0. Specifically, use the \u003ccode\u003emiddleware.RequireScopes(...)\u003c/code\u003e function on routes like \u003ccode\u003e/api/inbox\u003c/code\u003e, \u003ccode\u003e/api/panel/comments*\u003c/code\u003e, \u003ccode\u003e/api/addConnect\u003c/code\u003e, \u003ccode\u003e/api/delConnect/:id\u003c/code\u003e, \u003ccode\u003e/api/migration/*\u003c/code\u003e, and \u003ccode\u003e/api/backup/export\u003c/code\u003e as suggested in the advisory.\u003c/li\u003e\n\u003cli\u003eMove the \u003ccode\u003e/api/backup/export\u003c/code\u003e endpoint behind the authenticated router group and apply proper scope validation.\u003c/li\u003e\n\u003cli\u003eModify the \u003ccode\u003einternal/handler/backup/backup.go\u003c/code\u003e to preserve the existing authenticated viewer context (\u003ccode\u003ectx.Request.Context()\u003c/code\u003e) instead of rebuilding a new identity from raw JWT claims.\u003c/li\u003e\n\u003cli\u003eUpgrade Ech0 to version 4.3.5 or later to receive the official patch that addresses this vulnerability.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Ech0 Backup Export with Token Parameter\u003c/code\u003e to detect attempts to exploit the vulnerable \u003ccode\u003e/api/backup/export\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eReview and audit all privileged routes in Ech0 to ensure proper scope validation is enforced.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-09T12:00:00Z","date_published":"2024-01-09T12:00:00Z","id":"https://feed.craftedsignal.io/briefs/2024-01-ech0-token-bypass/","summary":"Ech0 scoped access tokens do not reliably enforce least privilege, leading to privilege escalation and data exfiltration by allowing low-scope admin tokens to access broader admin functionality, including backup exports.","title":"Ech0 Scoped Admin Access Token Bypass","url":"https://feed.craftedsignal.io/briefs/2024-01-ech0-token-bypass/"}],"language":"en","title":"CraftedSignal Threat Feed - Ech0","version":"https://jsonfeed.org/version/1.1"}