ZDF
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2025-40775

When an incoming DNS protocol message includes a Transaction Signature (TSIG), BIND always checks it.

Published May 21, 2025 · catalog updated May 23, 2025 · ISC BIND 9

Check this week

CVE-2025-40775 is not in CISA KEV. FIRST estimates a 15.30% chance of exploitation in the next 30 days. Check whether you run ISC BIND 9.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High7.5
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
15.30%
Remediation
Vendor / distro source
Affected products
vendor ISC BIND 9 9.20.0 ≤9.20.8

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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor ISC BIND 9 9.20.0 ≤9.20.89.20.0 ≤9.20.8

How to fix CVE-2025-40775

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

CVE-2025-40775 is not in CISA KEV. FIRST estimates a 15.30% chance of exploitation in the next 30 days. Check whether you run ISC BIND 9.

Which versions are affected?

Compare what you have installed with ISC BIND 9 9.20.0 ≤9.20.8 9.20.0 ≤9.20.8. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 15.30%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. May 23, 2025 · EUVD

    Updated

    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.

  2. Oct 17, 2026 · Arch Linux Security

    Detected

    CVE-2025-40775 is named on the public Arch Linux Security page.

Sources

  • Arch Linux SecurityVendor advisoryCVE-2025-40775

    CVE-2025-40775 is named on the public Arch Linux Security page.

    security.archlinux.org
  • CVE.orgVulnerability recordCVE-2025-40775

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-40775

    30-day exploitation probability 15.3%

    first.org
  • EUVDVulnerability recordEUVD-2025-16006

    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

    euvd.enisa.europa.eu

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.