NLnet Labs Unbound up to 1.26.1 resource consumption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k1.95

Summaryinfo

A vulnerability was found in NLnet Labs Unbound up to 1.26.1 and classified as critical. Affected by this issue is some unknown functionality. The manipulation results in resource consumption. This vulnerability is reported as CVE-2026-96405. The attack can be launched remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in NLnet Labs Unbound up to 1.26.1. Affected is an unknown code. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. CVE summarizes:

NLnet Labs Unbound up to and including version 1.26.1 limits compression-pointer traversal for each individual domain-name operation but has no aggregate inbound decompression-work budget. Many chained compression pointers in a message results in a lot of CPU usage following them. A malicious actor with recursive-query access and control of an ordinarily delegated authority that serves specially crafted replies can exploit the vulnerability and degrade Unbound's general performance.

The advisory is available at nlnetlabs.nl. This vulnerability is traded as CVE-2026-96405 since 10/14/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 1.26.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-107153). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

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: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (NLnet Labs): 🔒

CVSSv2info

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

Exploitinginfo

Class: Resource consumption
CWE: CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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: Unbound 1.26.2

Timelineinfo

10/14/2026 CVE reserved
10/21/2026 +7 days Advisory disclosed
10/21/2026 +0 days VulDB entry created
10/21/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: nlnetlabs.nl
Status: Confirmed

CVE: CVE-2026-96405 (🔒)
GCVE (CVE): GCVE-0-2026-96405
GCVE (VulDB): GCVE-100-424722
EUVD: 🔒

Entryinfo

Created: 10/21/2026 11:22
Updated: 10/21/2026 12:57
Changes: 10/21/2026 11:22 (62), 10/21/2026 12:57 (1)
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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