Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-123596— Hickory DNS through 0.26.0-alpha.1 DNSSEC Validation Bypass via Ancestor-Delegation NSEC

Quick assessment

Affected
hickory-dns hickory-dns
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Hickory DNS 的 版本从 0.26.0-alpha.1 到 0.26.0-alpha.1（含），以及 版本 0.26.0-beta.1 到 0.26.2 之前的版本中，存在一个 DNSSEC 验证缺陷。该缺陷位于验证递归解析器的 NSEC 记录处理器中：该处理器错误地将父区域侧的祖先委派 NSEC 记录（ancestor-delegation NSEC records）接受为区域切分（zone cut）下方名称不存在的证明。 处于通信路径上的攻击者、恶意的父名称服务器，或能够赢得端口与事务 ID（TXID

CVSS 8.8 · High

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-123596

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Hickory DNS through 0.26.0-alpha.1 DNSSEC Validation Bypass via Ancestor-Delegation NSEC
Source: CVE Program / CVE List V5
Vulnerability Description
Hickory DNS hickory-proto through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 contain a DNSSEC validation flaw in the validating recursor's NSEC handler that accepts parent-side ancestor-delegation NSEC records as proof of nonexistence for names below the zone cut. An on-path attacker, rogue parent nameserver, or attacker winning a port and TXID race can deliver one forged NXDOMAIN response built from genuinely signed parent NSEC records, causing authenticated denial of existing child-zone names cached for the negative TTL.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
对数据真实性的验证不充分
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
hickory-dns hickory-dns 0 ~ 0.26.0-alpha.1 -
hickory-dns hickory-dns 0.26.0-beta.1 ~ 0.26.2 -

II. Public POCs for CVE-2026-123596

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-123596

请登录查看更多情报信息。

Other References for CVE-2026-123596 (2)

Same Patch Batch · hickory-dns · 2026-11-08 · 39 CVEs total

CVE-2026-123595 8.8 HIGH Hickory DNS through 0.26.0-alpha.1 DNSSEC Validation Bypass via Ancestor-Delegation NSEC3
CVE-2026-123605 8.8 HIGH Hickory DNS through 0.25.0-alpha.3 DNSSEC Validation Bypass via RRSIG Signer's Name
CVE-2026-123570 7.5 HIGH Hickory DNS from 0.18 before 0.26.2 Memory Amplification DoS via RR Counts
CVE-2026-123572 7.5 HIGH Hickory-dns 0.20.1 before 0.26.2 Panic DoS via SVCB/HTTPS Zone Parser
CVE-2026-123575 7.5 HIGH Hickory DNS before 0.26.2 DoH Memory Exhaustion via Incomplete Request Bodies
CVE-2026-123571 7.5 HIGH Hickory DNS from 0.26.0 before 0.26.2 Panic via TSIG RDATA Decoding
CVE-2026-123577 7.5 HIGH Hickory DNS 0.24.0 before 0.26.2 DoH Unbounded Request Body Denial of Service
CVE-2026-123588 7.5 HIGH Hickory DNS Recursive Resolver Denial of Service via Cached Empty Connection Pool
CVE-2026-123574 7.5 HIGH Hickory DNS 0.24.0 before 0.26.2 Denial of Service via Zone File Parser
CVE-2026-123604 7.5 HIGH Hickory DNS 0.26.0-beta.1 before 0.26.2 Resource Exhaustion DoS via NameServerPool::try_se
CVE-2026-123576 7.5 HIGH Hickory DNS 0.24.0 through 0.26.1 Memory Exhaustion via DNS-over-QUIC Requests
CVE-2026-123573 7.5 HIGH hickory-dns from 0.20.1 before 0.26.2 Panic in SVCB/HTTPS Zone File Parser
CVE-2026-123606 7.5 HIGH Hickory-DNS Recursor 0.25.0-alpha.3 through 0.25.2 Glueless-NS Referral Amplification
CVE-2026-123607 7.5 HIGH Hickory DNS NSEC3 Closest-Encloser Proof Unbounded Loop Denial of Service
CVE-2026-123580 7.5 HIGH Hickory-DNS 0.26.0-beta.1 before 0.26.2 DNSSEC Nonexistence Proof Forgery via NSEC3
CVE-2026-123608 7.5 HIGH Hickory DNS hickory-proto 0.3.1 before 0.26.1 CPU Exhaustion via BinEncoder Name Compressi
CVE-2026-123586 7.5 HIGH Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals
CVE-2026-123587 6.8 MEDIUM Hickory-DNS 0.26.0 before 0.26.2 DNSSEC Nonexistence Forgery via Wraparound NSEC
CVE-2026-123603 6.5 MEDIUM Hickory DNS Missing IPv4-Mapped IPv6 Canonicalization Access Control Bypass
CVE-2026-123601 6.5 MEDIUM Hickory DNS 0.26.0-beta.1 before 0.26.2 NSEC3 Proof of Nonexistence Forgery

Showing top 20 of 39 CVEs. View all on vendor page → →

IV. Related Vulnerabilities

Same product: hickory-dns
Same vendor: hickory-dns
Same weakness: CWE-345