CVE-2026-19538: CWE-290 Authentication Bypass by Spoofing in NLnet Labs NSD
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.
CVE-2026-19538: CWE-290 Authentication Bypass by Spoofing in NLnet Labs NSD
Description
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 v4.0
Score 8.2high
Affected software
Weaknesses
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- NLnet Labs
- Date Reserved
- 2026-08-11T10:27:22.294Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8eacdfacd9273b49a440a0
Added to database: 08/26/2026, 09:07:43 UTC
Last updated: 08/26/2026, 10:22:21 UTC
Views: 5
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