Read the docs
TI-2026-39408 Aliases CVE-2026-54573

Authorization Bypass in API Key/OAuth Scopes via Path Parsing Discrepancy

Priority LOW 25CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-863.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00498 42nd percentileScored 2026-11-07
Fix Fixed outline (outline): 1.8.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
outlineoutlinebefore 1.8.01.8.0Patch availableCNA
  • outline Vendoroutline Affected before 1.8.0 Fixed in 1.8.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:getoutline:outline:*:*:*:*:*:*:*:*——outline
  • cpe:2.3:a:getoutline:outline:*:*:*:*:*:*:*:* Versions — — ·outline

Remediation

  • Fix · CNA outline (outline) Fixed in 1.8.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54573

References

Other 1

  • TI-2026-26021 Outline has a rate limit bypass that allows brute force of email login OTP CVSS 4.0CRITICAL 9.1
  • TI-2026-31952 Outline: Zip Extraction Path Escape via PATH_MAX Truncation in Collection Import CVSS 3.1HIGH 8.7
  • TI-2026-20086 Outline's IDOR allows unauthorized viewing and seizing of private deleted drafts CVSS 3.1HIGH 8.8
  • TI-2024-25167 An issue in Outline <= v0.76.1 allows attackers to execute a session hijacking attack via… CVSS 3.1HIGH 8.8
  • TI-2020-19165 Outline Service 1.3.3 - 'Outline Service ' Unquoted Service Path CVSS 4.0HIGH 8.5
  • TI-2026-83841 Outline exposes unpublished documents through public share links CVSS 4.0MEDIUM 6.9
See all 24 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences