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CVE-2026-123591

Hickory DNS 0.26.0-beta.1 before 0.26.2 DNSSEC Validation Bypass via Missing RFC 6840 Checks

CVSS score

8.2

EPSS probability

—

Risk score

0.8

Published

1 h ago

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

DayBreach AI Explanation

Verified against sources

Hickory DNS DNSSEC Validation Bypass Vulnerability

Sources read

2

Source agreement

0/2

Evidence confidence

%37

Short explanation

A vulnerability in Hickory DNS allows for a DNSSEC validation bypass due to missing checks required by RFC 6840 §4.4. Attackers can reuse child-side NSEC or NSEC3 records to fake an insecure delegation and forge child-zone records.

Why does it matter?

This vulnerability directly threatens DNS integrity, allowing attackers to tamper with DNS responses and forge data. Such integrity failures can lead to critical security risks, including the redirection of legitimate traffic to malicious destinations.

What should be done?

  • Follow vendor advisories and security updates
  • Update affected versions where applicable
Note on uncertainty

3 alanda kaynak uyuşmazlığı var. DayBreach bu değerleri saklamadı; kaynak karşılaştırması aşağıda gösteriliyor.

Chain of evidence and sources2 verified claims

Hickory DNS hickory-net 0.26.0-beta.1 ile 0.26.2 arasındaki ve hickory-proto 0.26.0-alpha.1 ve önceki sürümleri RFC 6840 §4.4 denetimlerini gerçekleştirememektedir.

Saldırganlar çocuk tarafındaki NSEC veya NSEC3 kayıtlarını yeniden kullanarak sahte bir güvensiz yetkilendirme üretebilir ve çocuk bölgesi kayıtlarını taklit edebilir.

Show the technical text from the sources

Hickory DNS hickory-net 0.26.0-beta.1 before 0.26.2 and hickory-proto through 0.26.0-alpha.1 fail to verify, per RFC 6840 §4.4, that an NSEC or NSEC3 record denying a DS RRset also proves the delegation's NS record exists. Attackers can reuse child-side NSEC or NSEC3 records to fake an insecure delegation and forge child-zone records.

CVSS vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

CWE: CWE-345

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-123591 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1hickory-dnshickory-dns View
2hickory-dnshickory-dns View
Total affected vendors: 1|Products: 2

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.2CVSS V4_0HIGHCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:NCVE CNA
8.2CVSS V40HIGHCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD
5.9CVSS V3_1MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NCVE CNA
5.9CVSS V31MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-123591 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-123591 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

8.2 / 10
Attack VectorNetworkComplexityHighPrivilegesNoneUser Interact.NoneConfidentialityHighIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)High
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

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Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

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CVE-2026-123591 · Hickory DNS 0.26.0-beta.1 before 0.26.2…