How severe is CVE-2026-5946?

CVE-2026-5946 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-5946 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5946?

CVE-2026-5946 affects Isc Bind. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5946?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-5946 have an EU (EUVD) identifier?

Yes. CVE-2026-5946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31107.

When was CVE-2026-5946 published?

CVE-2026-5946 was published on 2026-05-20 and last updated on 2026-06-30.

CVE-2026-5946

CVE-2026-5946 is a high-severity vulnerability in Isc Bind with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31107
Weakness: CWE-20
Affected product: Isc Bind
Published: 2026-05-20
Last modified: 2026-06-30

Description

Multiple flaws have been identified in `named` related to the handling of DNS messages whose CLASS is not Internet (`IN`) — for example, `CHAOS` or `HESIOD`, or DNS messages that specify meta-classes (`ANY` or `NONE`) in the question section. Specially crafted requests reaching the affected code paths — recursion, dynamic updates (`UPDATE`), zone change notifications (`NOTIFY`), or processing of `IN`-specific record types in non-`IN` data — can cause assertion failures in `named`. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.

Frequently asked questions

What is CVE-2026-5946?: Multiple flaws have been identified in `named` related to the handling of DNS messages whose CLASS is not Internet (`IN`) — for example, `CHAOS` or `HESIOD`, or DNS messages that specify meta-classes (`ANY` or `NONE`) in the question section. Specially crafted requests reaching the affected code paths — recursion, dynamic updates (`UPDATE`), zone change notifications (`NOTIFY`), or processing of `IN`-specific record types in non-`IN` data — can cause assertion failures in `named`. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.
How severe is CVE-2026-5946?: CVE-2026-5946 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-5946 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5946?: CVE-2026-5946 affects Isc Bind. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5946?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-5946 have an EU (EUVD) identifier?: Yes. CVE-2026-5946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31107.
When was CVE-2026-5946 published?: CVE-2026-5946 was published on 2026-05-20 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*

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