Hickory DNS up to 0.25.2 Recursive Resolver infinite loop

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.3$0-$5k0.00+

Summaryinfo

A vulnerability was found in Hickory DNS up to 0.25.2. It has been classified as critical. Impacted is an unknown function of the component Recursive Resolver. This manipulation causes infinite loop. This vulnerability is registered as CVE-2026-123586. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Hickory DNS up to 0.25.2. It has been declared as critical. Affected by this vulnerability is an unknown code block of the component Recursive Resolver. The manipulation with an unknown input leads to a infinite loop vulnerability. The CWE definition for the vulnerability is CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. As an impact it is known to affect availability. The summary by CVE is:

Hickory DNS 0.25.0-alpha.3 through 0.25.2 contains a query amplification vulnerability in its recursive resolver, which mishandles cyclic sibling name server referrals that lack glue records. Attackers controlling two zones whose name servers reference each other without glue records can make the recursor loop, sending many upstream queries, amplified further by zero-TTL NS records.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-123586 since 11/06/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

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

CNA Base Score: 7.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / 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: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/06/2026 CVE reserved
11/08/2026 +2 days Advisory disclosed
11/08/2026 +0 days VulDB entry created
11/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CNA: VulnCheck
CVE: CVE-2026-123586 (🔒)

GCVE (CVE): GCVE-0-2026-123586
GCVE (VulDB): GCVE-100-432745

Entryinfo

Created: 11/08/2026 03:27
Changes: 11/08/2026 03:27 (73)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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