Express Jwt
CVE-2020-15084
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Authorization verification
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.1 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system. |
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Alert meAnalysisAI
In express-jwt (NPM package) up and including version 5.3.3, the algorithms entry to be specified in the configuration is not being enforced. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified under CWE-285. In express-jwt (NPM package) up and including version 5.3.3, the algorithms entry to be specified in the configuration is not being enforced. When algorithms is not specified in the configuration, with the combination of jwks-rsa, it may lead to authorization bypass. You are affected by this vulnerability if all of the following conditions apply: - You are using express-jwt - You do not have algorithms configured in your express-jwt configuration. - You are using libraries such as jwks-rsa as the secret. You can fix this by specifying algorithms in the express-jwt configuration. See linked GHSA for example. This is also fixed in version 6.0.0. Affected products include: Auth0 Express-Jwt. Version information: version 5.3.3.
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
In express-jwt (NPM package) up and including version 5.3.3, the algorithms entry to be specified in the configuration is not being enforced. When algorithms is not specified in the configuration, with the combination of jwks-rsa, it may lead to authorization bypass. You are affected by this vulnerability if all of the following conditions apply: - You are using express-jwt - You do not have algorithms configured in your express-jwt configuration. - You are using libraries such as jwks-rsa as the secret. You can fix this by specifying algorithms in the express-jwt configuration. See linked GHSA for example. This is also fixed in version 6.0.0.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Exploit-DB