CVE-2026-33640

CRITICAL EPSS 37.0%
Published Mar 26, 20263mo ago · Modified Jun 17, 20261w ago
9.1 CVSS 4.0
Critical
Find Similar
Published Mar 26, 2026 3mo ago
Last Modified Jun 17, 2026 1w ago

Description

Outline is a service that allows for collaborative documentation. Outline implements an Email OTP login flow for users not associated with an Identity Provider. Starting in version 0.86.0 and prior to version 1.6.0, Outline does not invalidate OTP codes based on amount or frequency of invalid submissions, rather it relies on the rate limiter to restrict attempts. Consequently, identified bypasses in the rate limiter permit unrestricted OTP code submissions within the codes lifetime. This allows attackers to perform brute force attacks which enable account takeover. Version 1.6.0 fixes the issue.

CVSS Details

Base Score
9.1
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/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
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
37.0% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 1

CWE-307

Affected Products 1

VendorProductVersionRange
getoutlineoutline*≥0.86.0  –  <1.6.0

References 2

  • github.com https://github.com/outline/outline/releases/tag/v1.6.0
    Release Notes
  • github.com https://github.com/outline/outline/security/advisories/GHSA-cwhc-53hw-qqx6
    ExploitVendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.