CVE-2026-40012

MEDIUM

Published Jun 25, 2026 Modified Jun 25, 2026 CWE-524

Description

ECS zero scoped answers are stored in the packet cache while they should not. This impacts only configurations that have ECS enabled;

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CVSS v3.1 Score

5.3

MEDIUM

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

EPSS — Exploit Prediction

0.0031

Probability of exploitation

0.23%

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-524 CWE-524

References

Other References

https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-08.html

Frequently Asked Questions

What is CVE-2026-40012? +

ECS zero scoped answers are stored in the packet cache while they should not. This impacts only configurations that have ECS enabled; It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2026-40012? +

CVE-2026-40012 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0031, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-40012? +

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.

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