Outline is a service that allows for collaborative documentation. Prior to 1.7.1, the Slack integration callback for GET /auth/slack.post accepts an unsigned, session-independent OAuth state value. A third party who can obtain a Slack OAuth code for the same Outline Slack client can make a logged-in Outline user complete the callback and link that user's Outline account to the attacker's Slack team_id and user_id. The linked Slack identity can then use the Slack /outline search command as the victim Outline user. This vulnerability is fixed in 1.7.1.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.8, indicating it can be exploited remotely over the network but requires specific conditions to be met though user interaction is required requiring only low-level privileges . The vulnerability impacts confidentiality (data exposure), for affected systems. Impacting 1 product from getoutline organizations running these solutions should prioritize assessment and patching.
Reported in 2026, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2026-05-11T22:22:14.347
2026-05-15T20:21:42.197
Analyzed
CVSSv3.1: 5.8 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | getoutline | outline | < 1.7.1 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For getoutline's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.