5.4
MEDIUM CVSS 3.1
CVE-2026-123493
Vikunja from 2.4.0 before 2.7.1 Authentication Bypass via Bot API Tokens
Description

Vikunja from 2.4.0 before 2.7.1 contains an authentication bypass vulnerability that allows disabled or locked users to retain access through API tokens owned by their bot users. Because token validation only checks the bot's own status, attackers holding pre-minted bot tokens can keep reading and modifying shared projects via the HTTP API, CalDAV, MCP and feeds.

INFO

Published Date :

Nov. 8, 2026, 2:16 a.m.

Last Modified :

Nov. 8, 2026, 2:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-123493 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Vikunja vikunja
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update Vikunja to version 2.7.1 or later to fix authentication bypass for disabled users.
  • Update Vikunja to version 2.7.1 or later.
  • Review and revoke compromised API tokens.
  • Implement stricter token validation checks.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-123493.

URL Resource
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-5fc2-w2j4-6r8w
https://www.vulncheck.com/advisories/vikunja-from-2.4.0-before-2.7.1-authentication-bypass-via-bot-api-tokens
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-123493 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-123493 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-123493 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-123493 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 08, 2026

    Action Type Old Value New Value
    Added Description Vikunja from 2.4.0 before 2.7.1 contains an authentication bypass vulnerability that allows disabled or locked users to retain access through API tokens owned by their bot users. Because token validation only checks the bot's own status, attackers holding pre-minted bot tokens can keep reading and modifying shared projects via the HTTP API, CalDAV, MCP and feeds.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/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
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
    Added CWE CWE-613
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/123xxx/CVE-2026-123493.json">CVE-2026-123493</a>
    Added Reference https://github.com/go-vikunja/vikunja/security/advisories/GHSA-5fc2-w2j4-6r8w
    Added Reference https://www.vulncheck.com/advisories/vikunja-from-2.4.0-before-2.7.1-authentication-bypass-via-bot-api-tokens
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.