CVE-2025-30193Network attack vector

Service crash via TCP stack exhaustion

Published May 20, 2025 · Updated May 20, 2025

Uncontrolled recursion in PowerDNS DNSdist 1.9.9 and earlier allows remote attackers to crash the service via a crafted TCP exchange. When the per-connection query limit is unlimited, the TCP exchange drives repeated processing until the call stack is exhausted and the process terminates. The service is reachable without authentication, but only installations configured for unlimited queries on one incoming TCP connection are exposed; the consequence is a DNS proxy outage without system compromise.

CVSS severity7.5
High
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled recursion in PowerDNS DNSdist 1.9.9 and earlier allows remote attackers to crash the service via a crafted TCP exchange. When the per-connection query limit is unlimited, the TCP exchange drives repeated processing until the call stack is exhausted and the process terminates. The service is reachable without authentication, but only installations configured for unlimited queries on one incoming TCP connection are exposed; the consequence is a DNS proxy outage without system compromise.

The record

CVE
CVE-2025-30193
Published
May 20, 2025
Updated
May 20, 2025
Vendor
PowerDNS
Product
DNSdist
Classifications
CWE-674, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 20, 2025CVE publishedPublication date reported by the CVE source.
  2. May 20, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PowerDNS · DNSdistAffected versions are unavailable in this record.

Published CVSS scores

7.5PowerDNSCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-674Uncontrolled Recursion
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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