NIST deprecates RSA-2048 from 2030. Find every one of them before attackers do.
🛡️
Not in CISA KEV
HIGH severity

CVE-2026-123577 — Hickory-Dns

HIGH

CVE-2026-123577 is a high-severity (CVSS 7.5) CWE-770 vulnerability in hickory-dns hickory-dns. A fix is available — see the affected versions and patch details below.

Hickory DNS from 0.24.0 before 0.26.2 contains a resource exhaustion vulnerability that allows remote attackers to consume server memory via unbounded DoH request bodies. Attackers…

Published
Updated
Affected
1 product
Patched
See advisory
Exploits
None indexed
Exploitation data as of Nov 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Description

Hickory DNS from 0.24.0 before 0.26.2 contains a resource exhaustion vulnerability that allows remote attackers to consume server memory via unbounded DoH request bodies. Attackers can send large request bodies over HTTP/2 or HTTP/3 to a DNS over HTTP server, causing memory exhaustion and denial of service.

Affected Products

1 product · 1 configurations
Application
hickory-dnshickory-dns
< 0.26.2
1 version
0.24.0

Detection & mitigation playbook

Vendor / appliance

  1. Detect

    Inventory every hickory-dns hickory-dns deployment and check each version against the affected-products list above.

  2. Fix

    Apply the hickory-dns hickory-dns security patch or hotfix for CVE-2026-123577 on the affected version, following the vendor advisory for your exact build.

  3. Workarounds

    Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.

Frequently Asked Questions

Hickory DNS from 0.24.0 before 0.26.2 contains a resource exhaustion vulnerability that allows remote attackers to consume server memory via unbounded DoH request bodies. Attackers can send large request bodies over HTTP/2 or HTTP/3 to a DNS over HTTP server, causing memory exhaustion and denial of service.
O3 Security · Runtime Protection

Is CVE-2026-123577 being exploited in your environment?

Detect and block the exploit chain at execution, on systems you cannot patch yet.

Protect my workloads How runtime protection works
CVE-2026-123577: Hickory-Dns (High 7.5)