How severe is CVE-2020-25829?

CVE-2020-25829 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-2020-25829 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-25829?

CVE-2020-25829 primarily affects Powerdns Recursor. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-25829?

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.

When was CVE-2020-25829 published?

CVE-2020-25829 was published on 2020-10-16 and last updated on 2026-06-17.

CVE-2020-25829

CVE-2020-25829 is a high-severity vulnerability in Powerdns Recursor 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Powerdns Recursor
Published: 2020-10-16
Last modified: 2026-06-17

Description

An issue has been found in PowerDNS Recursor before 4.1.18, 4.2.x before 4.2.5, and 4.3.x before 4.3.5. A remote attacker can cause the cached records for a given name to be updated to the Bogus DNSSEC validation state, instead of their actual DNSSEC Secure state, via a DNS ANY query. This results in a denial of service for installation that always validate (dnssec=validate), and for clients requesting validation when on-demand validation is enabled (dnssec=process).

Frequently asked questions

What is CVE-2020-25829?: An issue has been found in PowerDNS Recursor before 4.1.18, 4.2.x before 4.2.5, and 4.3.x before 4.3.5. A remote attacker can cause the cached records for a given name to be updated to the Bogus DNSSEC validation state, instead of their actual DNSSEC Secure state, via a DNS ANY query. This results in a denial of service for installation that always validate (dnssec=validate), and for clients requesting validation when on-demand validation is enabled (dnssec=process).
How severe is CVE-2020-25829?: CVE-2020-25829 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-2020-25829 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-25829?: CVE-2020-25829 primarily affects Powerdns Recursor. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-25829?: 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.
When was CVE-2020-25829 published?: CVE-2020-25829 was published on 2020-10-16 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*
cpe:2.3:a:opensuse:backports_sle:15.0:sp1:*:*:*:*:*:*
cpe:2.3:a:opensuse:backports_sle:15.0:sp2:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

More vulnerabilities in Powerdns Recursor

CVE-2009-4009 — Critical (CVSS 10.0): Buffer overflow in PowerDNS Recursor before 3.1.7.2 allows remote attackers to cause a denial of service (daemon crash)…
CVE-2020-10030 — High (CVSS 8.8): An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough…
CVE-2025-59023 — High (CVSS 8.2): Crafted delegations or IP fragments can poison cached delegations in Recursor.
CVE-2019-3806 — High (CVSS 8.1): An issue has been found in PowerDNS Recursor versions after 4.1.3 before 4.1.9 where Lua hooks are not properly applied…
CVE-2015-5470 — High (CVSS 7.8): The label decompression functionality in PowerDNS Recursor before 3.6.4 and 3.7.x before 3.7.3 and Authoritative (Auth)…
CVE-2015-1868 — High (CVSS 7.8): The label decompression functionality in PowerDNS Recursor 3.5.x, 3.6.x before 3.6.3, and 3.7.x before 3.7.2 and…

All CVEs affecting Powerdns Recursor →