Authorization Bypass in API Key/OAuth Scopes via Path Parsing Discrepancy
Outline is a service that allows for collaborative documentation. Prior to 1.8.0, the AuthenticationHelper.canAccess function uses ctx.originalUrl to verify if an API key or OAuth token has the required scopes for a request. It extracts the resource by splitting the URL by / and taking the last segment. However, it fails to strip the URL fragment (#). Because Koa's router uses ctx.path (which strips the fragment) for routing, an attacker can append a fragment containing a permitted path (e.g., #foo/api/documents.info) to a restricted endpoint (e.g., /api/documents.create). The router will route the request to the restricted endpoint, but canAccess will evaluate the permitted path in the fragment, bypassing the API key scope restrictions and allowing privilege escalation. This vulnerability is fixed in 1.8.0.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-54573
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 2 Nov 2026, 21:09 UTC · Revision 1
Source evidence
Authorization Bypass in API Key/OAuth Scopes via Path Parsing Discrepancy
core-osv · Original sourcePublished 25 Jun 2026, 15:59 UTC
Outline is a service that allows for collaborative documentation. Prior to 1.8.0, the AuthenticationHelper.canAccess function uses ctx.originalUrl to verify if an API key or OAuth token has the required scopes for a request. It extracts the resource by splitting the URL by / and taking the last segment. However, it fails to strip the URL fragment (#). Because Koa's router uses ctx.path (which strips the fragment) for routing, an attacker can append a fragment containing a permitted path (e.g., #foo/api/documents.info) to a restricted endpoint (e.g., /api/documents.create). The router will route the request to the restricted endpoint, but canAccess will evaluate the permitted path in the fragment, bypassing the API key scope restrictions and allowing privilege escalation. This vulnerability is fixed in 1.8.0.
osv:CVE-2026-54573
Complete source record
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"id": "130c387dcbc32285a839f96efd8c405bc6d11ff107b186c7b890592cdf2ee4aa",
"url": "https://osv.dev/vulnerability/CVE-2026-54573",
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"title": "Authorization Bypass in API Key/OAuth Scopes via Path Parsing Discrepancy",
"summary": "Outline is a service that allows for collaborative documentation. Prior to 1.8.0, the AuthenticationHelper.canAccess function uses ctx.originalUrl to verify if an API key or OAuth token has the required scopes for a request. It extracts the resource by splitting the URL by / and taking the last segment. However, it fails to strip the URL fragment (#). Because Koa's router uses ctx.path (which strips the fragment) for routing, an attacker can append a fragment containing a permitted path (e.g., #foo/api/documents.info) to a restricted endpoint (e.g., /api/documents.create). The router will route the request to the restricted endpoint, but canAccess will evaluate the permitted path in the fragment, bypassing the API key scope restrictions and allowing privilege escalation. This vulnerability is fixed in 1.8.0.",
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"modified": "2026-10-28T02:30:23.693320759Z",
"provider": "osv",
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"source_id": "core-osv",
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"published_at": "2026-06-25T15:59:35.297+00:00"
}