CVE-2025-40775 describes an assertion failure vulnerability in BIND versions 9.20.0-9.20.8 and 9.21.0-9.21.7. This occurs when BIND processes an incoming DNS message with a Transaction Signature (TSIG) containing an invalid algorithm field, leading to an immediate service abortion. Rated 7.5 HIGH (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), this flaw allows an unauthenticated attacker to cause a denial of service with low attack complexity. Currently, there is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion surrounding this vulnerability.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
| ISC | BIND 9 | >= 9.20.0, <= 9.20.8, >= 9.21.0, <= 9.21.7CNA affecteddefault unaffected |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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