High severity · published Oct 22, 2025
CVE-2025-40778
Cache poisoning attacks with unsolicited RRs
8.6
CVSS
0.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
B9
BIND 9 · ISC
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; +1 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-40778
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-40778
kb.isc.org
https://kb.isc.org/docs/cve-2025-40778
www.openwall.com
http://www.openwall.com/lists/oss-security/2025/10/22/1
gist.github.com
https://gist.github.com/N3mes1s/f76b4a606308937b0806a5256bc1f918
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