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Vulnerability record · CVE-2025-40775 · published 21 May 2025

CVE-2025-40775: When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it.

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.

7.5 CVSS 3.1 High EPSS 15% · top 3.4% CWE-232 · CWE-232 Deferred
7.5CVSS 3.1 base score
15%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
3References
17 Jun 2026Last modified by NVD

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.

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

References

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Source: NIST National Vulnerability Database (record CVE-2025-40775), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.