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Status published
High
CVE-2025-40775
DNS message with invalid TSIG causes an assertion failure
Vulnerability Description
When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it. If the TSIG contains an invalid value in the algorithm field, BIND immediately aborts with an assertion failure. This issue affects BIND 9 versions 9.20.0 through 9.20.8 and 9.21.0 through 9.21.7.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
Affected Software
BIND 9
Vulnerable Versions:
9.20.0, 9.21.0
Timeline
Official Publish:
May 21st, 2025
Last Modified:
May 23rd, 2025
Added to House:
July 22nd, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weaknesses (CWE)
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.