VDB-382326 · CVE-2026-50045 · GCVE-0-2026-50045

NLnet Labs Unbound up to 1.25.1 DNSSEC allocation of resources

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.2	$0-$5k	4.69+

Summaryinfo

A vulnerability classified as critical was found in NLnet Labs Unbound up to 1.25.1. Affected is an unknown function of the component DNSSEC. The manipulation results in allocation of resources. This vulnerability is identified as CVE-2026-50045. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in NLnet Labs Unbound up to 1.25.1. It has been classified as critical. Affected is an unknown function of the component DNSSEC. The manipulation with an unknown input leads to a allocation of resources vulnerability. CWE is classifying the issue as CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. This is going to have an impact on availability. CVE summarizes:

In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a single client query for a deeply nested name under a DNSSEC-signed parent can cause Unbound to send more upstream packets per client query than the configured 'max-global-quota'. This effectively bypasses a security configuration that limits upstream amplification traffic.

The advisory is available at nlnetlabs.nl. This vulnerability is traded as CVE-2026-50045 since 06/22/2026. 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 1.25.2 eliminates this vulnerability.

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Productinfo

Vendor

NLnet Labs

Name

Unbound

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.2

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

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Unbound 1.25.2

Timelineinfo

06/22/2026 CVE reserved
07/22/2026 +30 days Advisory disclosed
07/22/2026 +0 days VulDB entry created
07/22/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: nlnetlabs.nl
Status: Confirmed

CVE: CVE-2026-50045 (🔒)
GCVE (CVE): GCVE-0-2026-50045
GCVE (VulDB): GCVE-100-382326

Entryinfo

Created: 07/22/2026 15:56
Changes: 07/22/2026 15:56 (53)
Complete: 🔍
Cache ID: 216::103