How severe is CVE-2026-40210?

CVE-2026-40210 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.

Is CVE-2026-40210 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40210?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-40210 have an EU (EUVD) identifier?

Yes. CVE-2026-40210 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39349.

When was CVE-2026-40210 published?

CVE-2026-40210 was published on 2026-06-25.

CVE-2026-40210

CVE-2026-40210 is a medium-severity vulnerability with a CVSS 3.x base score of 4.8. 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-126.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39349
Weakness: CWE-126
Published: 2026-06-25
Last modified: 2026-06-25

Description

An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.

Frequently asked questions

What is CVE-2026-40210?: An out-of-bounds read might happen when SetMacAddrAction is used, potentially resulting in uninitialized memory being sent over the network or a crash.
How severe is CVE-2026-40210?: CVE-2026-40210 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.
Is CVE-2026-40210 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40210?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-40210 have an EU (EUVD) identifier?: Yes. CVE-2026-40210 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39349.
When was CVE-2026-40210 published?: CVE-2026-40210 was published on 2026-06-25.

References

https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html

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