CVE-2026-19538
High
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.
SeverityHigh
CVSS7.5
Exploit probability—
ProductNlnetlabs Nsd
PublishedAug 26, 2026
First seenAug 26, 2026
Weakness typeCWE-290CWE-290CWE-672CWE-672
How to fix
Update
- nlnetlabs nsd4.15.1 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| nlnetlabs nsd | 4.8.0 ≤ v < 4.15.1 | 4.15.1 |
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