CVE-2026-19538

The BLOCKED access control list items that are evaluated to deny access on the the proxy protocol port can be bypassed completely when connecting over TCP or TLS and sending the query twice on connection that is kept open.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-19538.txt	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-26 09:16

Updated : 2026-09-08 19:59

NVD link : CVE-2026-19538

Mitre link : CVE-2026-19538

CVE.ORG link : CVE-2026-19538

JSON object : View

Products Affected

nlnetlabs

nsd

CWE

CWE-290

Authentication Bypass by Spoofing

CWE-672

Operation on a Resource after Expiration or Release

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