node-oauth oauth2-server up to 5.2.x code_verifier excessive authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in node-oauth oauth2-server up to 5.2.x. Impacted is an unknown function. Performing a manipulation of the argument code_verifier results in excessive authentication. This vulnerability is cataloged as CVE-2026-41213. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in node-oauth oauth2-server up to 5.2.x. This affects an unknown functionality. The manipulation of the argument code_verifier with an unknown input leads to a excessive authentication vulnerability. CWE is classifying the issue as CWE-307. The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame, making it more susceptible to brute force attacks. This is going to have an impact on confidentiality. The summary by CVE is:

@node-oauth/oauth2-server is a module for implementing an OAuth2 server in Node.js. The token exchange path accepts RFC7636-invalid code_verifier values (including one-character strings) for S256 PKCE flows. Because short/weak verifiers are accepted and failed verifier attempts do not consume the authorization code, an attacker who intercepts an authorization code can brute-force code_verifier guesses online until token issuance succeeds.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-41213 since 04/18/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1110.001 according to MITRE ATT&CK.

Upgrading to version 5.3.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25272). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.9
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Excessive authentication
CWE: CWE-307 / CWE-799 / CWE-400
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: oauth2-server 5.3.0

Timelineinfo

04/18/2026 CVE reserved
04/23/2026 +5 days Advisory disclosed
04/23/2026 +0 days VulDB entry created
04/25/2026 +2 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-jhm7-29pj-4xvf
Status: Confirmed

CVE: CVE-2026-41213 (🔒)
GCVE (CVE): GCVE-0-2026-41213
GCVE (VulDB): GCVE-100-359199
EUVD: 🔒

Entryinfo

Created: 04/23/2026 23:13
Updated: 04/25/2026 11:45
Changes: 04/23/2026 23:13 (65), 04/25/2026 11:45 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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