Is CVE-2026-123608 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-123608 being exploited in the wild.

How severe is CVE-2026-123608?

High severity, with a CVSS score of 7.5, published 8 November 2026.

Which products and versions are affected?

Hickory-Dns Hickory-Proto 0.3.1 through 0.26.0.

Is there a fix for CVE-2026-123608?

Yes: fixed in 0.26.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-123608 attacked?

It is attacked over the network.

Am I affected by CVE-2026-123608?

Check whether you run Hickory-Dns Hickory-Proto at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-123608: Hickory DNS hickory-proto denial of service in BinEncoder

CVE-2026-123608 · Severity: high · CVSS 7.5 · Published 2026-11-08

Hickory DNS is a DNS client library used in Rust applications. A flaw in its message encoding function allows attackers to send specially crafted DNS messages that consume excessive CPU, causing denial of service by exhausting server resources. This can impact any service relying on hickory-proto to process DNS messages.

Technologies: Hickory-Dns Hickory-Proto. Vendors: Hickory-Dns.

Quick answers

Is CVE-2026-123608 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-123608 being exploited in the wild.
How severe is CVE-2026-123608?: High severity, with a CVSS score of 7.5, published 8 November 2026.
Which products and versions are affected?: Hickory-Dns Hickory-Proto 0.3.1 through 0.26.0.
Is there a fix for CVE-2026-123608?: Yes: fixed in 0.26.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-123608 attacked?: It is attacked over the network.
Am I affected by CVE-2026-123608?: Check whether you run Hickory-Dns Hickory-Proto at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 0.26.1

Technical details

The BinEncoder component in hickory-proto uses an O(n²) algorithm for DNS name compression, storing candidate labels in a vector and performing linear scans to find matches. An attacker can craft a malicious DNS message with many records to introduce numerous candidate labels and trigger the linear scan repeatedly, amplifying CPU exhaustion. The vulnerability exists in versions 0.3.1 through 0.26.0 and requires network access to send the malicious message.

Affected products

Hickory DNS hickory-proto 0.3.1 through 0.26.0

Timeline

2026-05-01: disclosed
2026-11-08: advisory

References

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