CVE-2026-123572 (CVSS 7.5)

Description

Hickory-dns from 0.20.1 before 0.26.2 contains a denial of service vulnerability in the hickory-proto SVCB and HTTPS record presentation format parser, which panics on malformed alpn values. Attackers can supply untrusted zone files with unbalanced quotes, consecutive commas, or invalid escapes in alpn parameters to crash parsing processes.

Is your site exposed to CVE-2026-123572?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0034

Probability of exploitation

0.28%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-1286 CWE-1286

References

Other References

https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-hx8c-fjhc-hmf5 https://www.vulncheck.com/advisories/hickory-dns-0.20.1-before-0.26.2-panic-dos-via-svcb-https-zone-parser

Frequently Asked Questions

What is CVE-2026-123572? +

Hickory-dns from 0.20.1 before 0.26.2 contains a denial of service vulnerability in the hickory-proto SVCB and HTTPS record presentation format parser, which panics on malformed alpn values. Attackers can supply untrusted zone files with unbalanced quotes, consecutive commas, or invalid escapes in alpn parameters to crash parsing processes. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-123572? +

CVE-2026-123572 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0034, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-123572? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-105660

Improper Validation of Syntactic Correctness of Input vulnerability in mtrudel bandit allows an unauthenticated remote attacker to set conn.host and …

CVE-2026-83611

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. Prior to @xmldom/xmldom versions …

CVE-2026-111107

A NULL pointer dereference vulnerability in WatchGuard Fireware OS’s management interface allows a remote, unauthenticated attacker with network access to …

CVE-2026-88260

Authentication bypass using an alternate path or channel and Improper validation of syntactic correctness of input vulnerability in Brainzcompany Zenius …

CVE-2026-67418

RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.19, 4.0.24, 4.1.15, 4.2.10, and 4.3.5, the MQTT 5 parser …

CVE-2026-0983

Denial-of-service condition in M-Files Server versions before 26.5.16015.0, before 26.2 LTS, and before 25.8 LTS SR3 allows an authenticated user …