CVE-2025-40778

HIGH 8.6

Cache poisoning attacks with unsolicited RRs

CVSS Score

8.6

EPSS Score

0.0%

EPSS Percentile

0th

Under certain circumstances, BIND is too lenient when accepting records from answers, allowing an attacker to inject forged data into the cache. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.

CWE	CWE-349
Vendor	isc
Product	bind 9
Published	Oct 22, 2025
Last Updated	Feb 26, 2026

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CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

High

Availability

None

Affected Versions

ISC / BIND 9

9.11.0 ≤ 9.16.50 9.18.0 ≤ 9.18.39 9.20.0 ≤ 9.20.13 9.21.0 ≤ 9.21.12 9.11.3-S1 ≤ 9.16.50-S1 9.18.11-S1 ≤ 9.18.39-S1 9.20.9-S1 ≤ 9.20.13-S1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

kb.isc.org: https://kb.isc.org/docs/cve-2025-40778 gist.github.com: https://gist.github.com/N3mes1s/f76b4a606308937b0806a5256bc1f918 openwall.com: http://www.openwall.com/lists/oss-security/2025/10/22/1

Credits

ISC would like to thank Yuxiao Wu, Yunyi Zhang, Baojun Liu, and Haixin Duan from Tsinghua University for bringing this vulnerability to our attention.