CVE-2025-40775
published 2025-05-21CVE-2025-40775: 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…
PriorityP349high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
12.34%
95.8th percentile
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.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | bind9 | < bind9 1:9.20.9-1 (forky) | bind9 1:9.20.9-1 (forky) |
| isc | bind | >= 0 < 9.18.37-r0 | 9.18.37-r0 |
| isc | bind | >= 0 < 9.18.37-r0 | 9.18.37-r0 |
| isc | bind | >= 0 < 9.18.37-r0 | 9.18.37-r0 |
| isc | bind | >= 0 < 9.18.37-r0 | 9.18.37-r0 |
| isc | bind | >= 0 < 9.20.9-r0 | 9.20.9-r0 |
| isc | bind | >= 0 < 9.20.9-r0 | 9.20.9-r0 |
| isc | bind9 | >= 0 < 1:9.20.9-1 | 1:9.20.9-1 |
| isc | bind9 | >= 0 < 1:9.20.9-1 | 1:9.20.9-1 |
| isc | bind_9 | 9.20.0 – 9.20.8 | — |
| isc | bind_9 | 9.21.0 – 9.21.7 | — |
| msrc | azl3_bind_9.20.5-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_bind_9.20.9-1_on_azure_linux_3.0 | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5LOW
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
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OSV
CVE-2025-40775: When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it
osv·2025-05-21·CVSS 7.5
CVE-2025-40775 [HIGH] 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.
OSV
CVE-2025-40775: When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it
osv·2025-05-21·CVSS 7.5
CVE-2025-40775 [HIGH] 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.
GHSA
GHSA-gqgx-hgvf-f75f: When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it
ghsa_unreviewed·2025-05-21
CVE-2025-40775 [HIGH] CWE-232 GHSA-gqgx-hgvf-f75f: 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.
Ubuntu
Bind vulnerability
vendor_ubuntu·2025-05-21
CVE-2025-40775 Bind vulnerability
Title: Bind vulnerability
Summary: Bind could be made to crash if it received specially crafted network
traffic.
It was discovered that Bind incorrectly handled certain DNS messages with
invalid TSIG. A remote attacker could possibly use this issue to cause Bind
to crash, resulting in a denial of service.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
bind: DNS message with invalid TSIG causes an assertion failure
vendor_redhat·2025-05-21·CVSS 7.5
CVE-2025-40775 [HIGH] CWE-617 bind: DNS message with invalid TSIG causes an assertion failure
bind: DNS message with invalid TSIG causes an assertion failure
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.
An assertion failure vulnerability was found in the BIND package. 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. By sending specific messages to the server, an attacker can cause named to terminate unexpectedly, causing a denial of service.
Statement: No Red Hat pro
Microsoft
DNS message with invalid TSIG causes an assertion failure
vendor_msrc·2025-05-13·CVSS 7.5
CVE-2025-40775 [HIGH] CWE-232 DNS message with invalid TSIG causes an assertion failure
DNS message with invalid TSIG causes an assertion failure
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
isc: isc
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.m
Debian
CVE-2025-40775: bind9 - When an incoming DNS protocol message includes a Transaction Signature (TSIG), B...
vendor_debian·2025·CVSS 7.5
CVE-2025-40775 [HIGH] CVE-2025-40775: bind9 - When an incoming DNS protocol message includes a Transaction Signature (TSIG), B...
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.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved (fixed in 1:9.20.9-1)
sid: resolved (fixed in 1:9.20.9-1)
trixie: resolved (fixed in 1:9.20.9-1)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-05-21
Published