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- Published
- Apr 22, 2026
- Updated
- Jun 17, 2026
- EPSS
- 0.5% · 38th percentile
- CWE
- CWE-476
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Report tools
Action score
23
Monitor
Low priority for now.
- CVSS
- 23 / 40 · 5.9 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 5.9
- CNA · OX
- 5.9
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| powerdns | recursor | cpe:2.3:a:powerdns:recursor |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- powerdns recursor5.2.0 and later · before 5.2.9
- powerdns recursor5.3.0 and later · before 5.3.6
- powerdns recursor5.4.0
Versions reported by the vendor
Affected version ranges reported by the assigning authority (OX). Independent of NVD's CPE analysis and usually ahead of it.
PowerDNS Recursor
- 5.4.0 and later · before 5.4.1affected · semver
- 5.3.0 and later · before 5.3.6affected · semver
- 5.2.0 and later · before 5.2.9affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | pdns-recursor | all versions | — |
| Debian:13 | pdns-recursor | before 5.2.9-0+deb13u1 | 5.2.9-0+deb13u1 |
| Debian:14 | pdns-recursor | before 5.4.1-1 | 5.4.1-1 |
Same product
powerdns: all recordsOther highest-scoring records for the same primary product.
- CVE-2018-16855An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds m48Plan
- CVE-2017-15120An issue has been found in the parsing of authoritative answers in PowerDNS Recursor before 4.0.8, leading to a NULL pointer dereference whe45Plan
- CVE-2009-4009Buffer overflow in PowerDNS Recursor before 3.1.7.2 allows remote attackers to cause a denial of service (daemon crash) or possibly execute 45Plan
- CVE-2020-10030An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0.42Plan
- CVE-2014-8601PowerDNS Recursor before 3.6.2 does not limit delegation chaining, which allows remote attackers to cause a denial of service ("performance 41Plan
- CVE-2019-3807An issue has been found in PowerDNS Recursor versions 4.1.x before 4.1.9 where records in the answer section of responses received from auth39Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| PowerDNS Recursor | 5.2.9 | Vendor (CNA) |
| PowerDNS Recursor | 5.3.6 | Vendor (CNA) |
| PowerDNS Recursor | 5.4.1 | Vendor (CNA) |
| debian:pdns-recursor | 5.2.9-0+deb13u1 · Debian:13 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- ylwango613finder
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2025-30195380 days apartA crafted zone can lead to an illegal memory access in the PowerDNS Recursor30Monitor
- CVE-2026-336000 days apartNull pointer dereference in RPZ transfer19Monitor
- CVE-2026-336010 days apartInsufficient validation of zonemd record19Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-476 · NULL Pointer DereferenceCVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.