Deno up to 2.1.1 Authorization Header fetch information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Deno up to 2.1.1. This affects the function fetch of the component Authorization Header Handler. This manipulation causes information disclosure. This vulnerability is tracked as CVE-2025-21620. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Deno up to 2.1.1. It has been declared as problematic. Affected by this vulnerability is the function fetch of the component Authorization Header Handler. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. The summary by CVE is:

Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. When you send a request with the Authorization header to one domain, and the response asks to redirect to a different domain, Deno'sfetch() redirect handling creates a follow-up redirect request that keeps the original Authorization header, leaking its content to that second domain. This vulnerability is fixed in 2.1.2.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2025-21620 since 12/29/2024. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

Upgrading to version 2.1.2 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (GitHub_M): 🔍

CVSSv2info

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

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
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: Deno 2.1.2

Timelineinfo

12/29/2024 🔍
01/07/2025 +9 days 🔍
01/07/2025 +0 days 🔍
01/07/2025 +0 days 🔍

Sourcesinfo

Advisory: GHSA-f27p-cmv8-xhm6
Status: Confirmed

CVE: CVE-2025-21620 (🔍)
GCVE (CVE): GCVE-0-2025-21620
GCVE (VulDB): GCVE-100-290347

Entryinfo

Created: 01/07/2025 06:49
Updated: 01/07/2025 09:30
Changes: 01/07/2025 06:49 (65), 01/07/2025 09:30 (4)
Complete: 🔍
Cache ID: 216::103

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