CVE-2026-40103 Vulnerability Analysis & Exploit Details

CVE-2026-40103
Vulnerability Scoring

4.3
/10
Medium Risk

The vulnerability CVE-2026-40103 could compromise system integrity but typically requires user interaction to be exploited.

Attack Complexity Details

  • Attack Complexity: Low
    Exploits can be performed without significant complexity or special conditions.
  • Attack Vector: Network
    Vulnerability is exploitable over a network without physical access.
  • Privileges Required: Low
    Some privileges are necessary to exploit the vulnerability.
  • Scope: Unchanged
    Exploit remains within the originally vulnerable component.
  • User Interaction: None
    No user interaction is necessary for exploitation.

CVE-2026-40103 Details

Status: Undergoing Analysis

Last updated: 🕒 13 Apr 2026, 15:02 UTC
Originally published on: 🕔 10 Apr 2026, 17:17 UTC

Time between publication and last update: 2 days

CVSS Release: version 3

CVSS3 Source

security-advisories@github.com

CVSS3 Type

Secondary

CVSS3 Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

CVE-2026-40103 Vulnerability Summary

CVE-2026-40103: Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, Vikunja's scoped API token enforcement for custom project background routes is method-confused. A token with only projects.background can successfully delete a project background, while a token with only projects.background_delete is rejected. This is a scoped-token authorization bypass. This vulnerability is fixed in 2.3.0.

Assessing the Risk of CVE-2026-40103

Access Complexity Graph

The exploitability of CVE-2026-40103 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).

Exploitability Analysis for CVE-2026-40103

CVE-2026-40103 presents an accessible attack vector with minimal effort required. Restricting access controls and implementing security updates are critical to reducing exploitation risks.

Understanding AC and PR

A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.

Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.

Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.

CVSS Score Breakdown Chart

Above is the CVSS Sub-score Breakdown for CVE-2026-40103, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.

CIA Impact Analysis

Below is the Impact Analysis for CVE-2026-40103, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: None
    CVE-2026-40103 has no significant impact on data confidentiality.
  • Integrity: Low
    Exploiting CVE-2026-40103 may cause minor changes to data without severely impacting its accuracy.
  • Availability: None
    CVE-2026-40103 does not impact system availability.

CVE-2026-40103 References

External References

CWE Common Weakness Enumeration

CWE-836

CAPEC Common Attack Pattern Enumeration and Classification

  • Use of Captured Hashes (Pass The Hash) CAPEC-644 An adversary obtains (i.e. steals or purchases) legitimate Windows domain credential hash values to access systems within the domain that leverage the Lan Man (LM) and/or NT Lan Man (NTLM) authentication protocols.
  • Use of Known Kerberos Credentials CAPEC-652 An adversary obtains (i.e. steals or purchases) legitimate Kerberos credentials (e.g. Kerberos service account userID/password or Kerberos Tickets) with the goal of achieving authenticated access to additional systems, applications, or services within the domain.

Protect Your Infrastructure against CVE-2026-40103: Combat Critical CVE Threats

Stay updated with real-time CVE vulnerabilities and take action to secure your systems. Enhance your cybersecurity posture with the latest threat intelligence and mitigation techniques. Develop the skills necessary to defend against CVEs and secure critical infrastructures. Join the top cybersecurity professionals safeguarding today's infrastructures.

Other 5 Recently Published CVEs Vulnerabilities

  • CVE-2026-6483 – A vulnerability was found in Wavlink WL-WN530H4 20220721. This vulnerability affects the function strcat/snprintf of the file /cgi-bin/internet.cgi...
  • CVE-2026-5131 – GREENmod uses named pipes for communication between plugins, the web portal, and the system service, but the access control lists for these pipes a...
  • CVE-2026-35153 – Dell PowerProtect Data Domain, versions 7.7.1.0 through 8.7.0.0, LTS2025 release versions 8.3.1.0 through 8.3.1.20, LTS2024 release versions 7.13.1...
  • CVE-2026-35074 – Dell PowerProtect Data Domain, versions 7.7.1.0 through 8.7.0.0, LTS2025 release versions 8.3.1.0 through 8.3.1.20, LTS2024 release versions 7.13.1...
  • CVE-2026-35073 – Dell PowerProtect Data Domain, versions 7.7.1.0 through 8.7.0.0, LTS2025 release versions 8.3.1.0 through 8.3.1.20, LTS2024 release versions 7.13.1...