CVE-2025-30194

Denial of service via crafted DoH exchange

HIGH
7.5
CVSS Score
Published: April 29, 2025 at 11:25 AM UTC
Updated: June 17, 2026 at 09:08 AM UTC
2 products affected across 1 vendorAuthoritativeDNSdist

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Severity
HIGH7.5
Exploit prediction
EPSS 2%
SSVC
No known exploit

Description

When DNSdist is configured to provide DoH via the nghttp2 provider, an attacker can cause a denial of service by crafting a DoH exchange that triggers an illegal memory access (double-free) and crash of DNSdist, causing a denial of service. The remedy is: upgrade to the patched 1.9.9 version. A workaround is to temporarily switch to the h2o provider until DNSdist has been upgraded to a fixed version. We would like to thank Charles Howes for bringing this issue to our attention.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

1.9.0 ≤ v < 1.9.91.9.0
Affected range stops below 1.9.9, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHOX
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-416

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