dbcve.org
Incorrect AuthorizationWeakness · CWE-863

CVE-2026-54573

MEDIUM · 5.3 CVSS v4.0 Published 2026-06-25
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
59/100
Remediation priority · Elevated
Remotely reachable Zero-click 8 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

In Outline prior to 1.8.0, the AuthenticationHelper.canAccess function uses ctx.originalUrl to verify API key/OAuth token scopes but fails to strip URL fragments (#). Since Koa's router uses ctx.path (which strips fragments), 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 routes to the restricted endpoint, but canAccess evaluates the permitted path in the fragment, bypassing scope restrictions and achieving privilege escalation.

MitigationUpgrade Outline to version 1.8.0 or later, which includes the fix to strip URL fragments before scope validation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Outline version
    Check the installed Outline version by examining package.json, docker image tags, or the /api/status endpoint if available
    Affected if The installed version is prior to 1.8.0
  2. Confirm API or OAuth authentication is in use
    Review authentication configuration to determine if API keys or OAuth tokens are enabled for theOutline instance
    Affected if API key or OAuth authentication is enabled and the version is below 1.8.0
  3. Inspect AuthenticationHelper.canAccess implementation
    Examine the source code of the AuthenticationHelper.canAccess function in the Outline codebase, looking for usage of ctx.originalUrl for scope validation
    Affected if The code uses ctx.originalUrl (which includes fragments) rather than ctx.path (which strips fragments) for scope checks
  4. Verify URL fragment handling in routing
    Test the routing behavior by sending a request with a fragment appended to a restricted endpoint, such as /api/documents.create#allowedPath
    Affected if Requests with fragments bypass scope validation and return unexpected access patterns

A defender is affected if running Outline versions before 1.8.0 with API key or OAuth authentication enabled, and the canAccess function uses ctx.originalUrl for scope validation without stripping fragments first.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade Outline to version 1.8.0 or later, which includes the fix to strip URL fragments before scope validation.

Recommended fix High confidence

1.8.0

  1. Upgrade Outline to version 1.8.0 or later to resolve the authorization bypass vulnerability where URL fragments could be used to bypass API key scope restrictions

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing3.0 h
  • Review / QA2.0 h
8.0 hours of engineering $1,390
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,224.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-54573 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-54573 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data