# CVE-2025-40776

## Summary

- **CVE ID:** CVE-2025-40776
- **Severity:** HIGH
- **CVSS Score:** 8.6 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N)
- **CWE:** CWE-349
- **Published:** Jul 16, 2025
- **Last Modified:** Mar 12, 2026

## Description

A `named` caching resolver that is configured to send ECS (EDNS Client Subnet) options may be vulnerable to a cache-poisoning attack.
This issue affects BIND 9 versions 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.37-S1, and 9.20.9-S1 through 9.20.10-S1.

## Affected Products

- ISC — BIND 9 (9.11.3-S1)
- ISC — BIND 9 (9.18.11-S1)
- ISC — BIND 9 (9.20.9-S1)
- ISC — BIND 9 (9.0.0)

## References

- [CNA](https://kb.isc.org/docs/cve-2025-40776)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.21%
- **EPSS Percentile:** 10.9

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._