denoland deno up to 2.8.0 Domain fetch protection mechanism

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k2.47-

Summaryinfo

A vulnerability categorized as problematic has been discovered in denoland deno up to 2.8.0. Affected by this vulnerability is the function fetch of the component Domain Handler. Such manipulation leads to protection mechanism. This vulnerability is referenced as CVE-2026-49859. The attack can only be performed from a local environment. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in denoland deno up to 2.8.0 and classified as problematic. Affected by this issue is the function fetch of the component Domain Handler. The manipulation with an unknown input leads to a protection mechanism vulnerability. Using CWE to declare the problem leads to CWE-693. The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, when fetch() was called, Deno checked the destination hostname against --deny-net rules but did not re-check the IP addresses that hostname resolved to. An attacker-controlled script could use a specially crafted domain name that passes the hostname check yet resolves to a denied IP, bypassing the network restriction entirely. This vulnerability is fixed in 2.8.1.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-49859 since 06/02/2026. The exploitation is known to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit.

Upgrading to version 2.8.1 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

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

CNA Base Score: 5.2
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: Protection mechanism
CWE: CWE-693
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
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 2.8.1

Timelineinfo

06/02/2026 CVE reserved
06/23/2026 +21 days Advisory disclosed
06/23/2026 +0 days VulDB entry created
06/23/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-cpgj-f7g3-2pp2
Status: Confirmed

CVE: CVE-2026-49859 (🔒)
GCVE (CVE): GCVE-0-2026-49859
GCVE (VulDB): GCVE-100-373010

Entryinfo

Created: 06/23/2026 23:40
Changes: 06/23/2026 23:40 (65)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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