What is the CVSS score of CVE-2020-15234?

CVE-2020-15234 has a CVSS 3.1 base score of 4.8 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.8%.

Is there a patch available for CVE-2020-15234?

Yes, a patch is available for CVE-2020-15234. Update the affected software to the latest version immediately.

Fosite CVE-2020-15234

MEDIUM

Improper Input Validation (CWE-20)

2020-10-02 security-advisories@github.com

Information Disclosure Fosite Ory

4.8

CVSS 3.1 · NVD

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Vulnerability Assessment

Weakness	CWE CWE-20 OWASP Top 10:2025 A05:2025 - Injection ASVS 5.0 V2 - Validation and Business Logic Input validation, allowlisting
Impact	CVSS score of 4.8 (MEDIUM). Attack characteristics: network attack vector, low complexity, high privileges required, user interaction required.
Exploit ScenarioDerived	This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).

Patch available 0.8% exploitation probability (EPSS)

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AnalysisAI

ORY Fosite is a security first OAuth2 & OpenID Connect framework for Go. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, 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

go github.com/ory/fosite fix: 0.34.1

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in go

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-20. ORY Fosite is a security first OAuth2 & OpenID Connect framework for Go. In Fosite before version 0.34.1, the OAuth 2.0 Client's registered redirect URLs and the redirect URL provided at the OAuth2 Authorization Endpoint where compared using strings.ToLower while they should have been compared with a simple string match. This allows an attacker to register a client with allowed redirect URL https://example.com/callback. Then perform an OAuth2 flow and requesting redirect URL https://example.com/CALLBACK. Instead of an error (invalid redirect URL), the browser is redirected to https://example.com/CALLBACK with a potentially successful OAuth2 response, depending on the state of the overall OAuth2 flow (the user might still deny the request for example). This vulnerability has been patched in ORY Fosite v0.34.1. Affected products include: Ory Fosite. Version information: version 0.34.1.

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Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 4.8 MEDIUM

AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

DescriptionNVD

ORY Fosite is a security first OAuth2 & OpenID Connect framework for Go. In Fosite before version 0.34.1, the OAuth 2.0 Client's registered redirect URLs and the redirect URL provided at the OAuth2 Authorization Endpoint where compared using strings.ToLower while they should have been compared with a simple string match. This allows an attacker to register a client with allowed redirect URL https://example.com/callback. Then perform an OAuth2 flow and requesting redirect URL https://example.com/CALLBACK. Instead of an error (invalid redirect URL), the browser is redirected to https://example.com/CALLBACK with a potentially successful OAuth2 response, depending on the state of the overall OAuth2 flow (the user might still deny the request for example). This vulnerability has been patched in ORY Fosite v0.34.1.

Threat Intelligence Overview

EPSS Score

0.8%

Top 47% exploitable

Data Quality

3 sources

Confidence: Low

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.

SignalValue

Severity MEDIUM

CISA KEV No

Public POC No

EPSS 0.8%

Patch available Yes

Active threat No

Deciding rule

MEDIUM severity (CVSS 4.0-6.9)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

None

System Exposure· derived

Open

Automatable· derived

Human Impact· derived

Medium

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +1

CVSS: +24

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.