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CVE-2026-50045 (GCVE-0-2026-50045)

Vulnerability from cvelistv5 – Published: 2026-07-22 13:07 – Updated: 2026-07-22 18:57
VLAI
Title
'max-global-quota' reset by DNSSEC validation restarts
Summary
In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, a single client query for a deeply nested name under a DNSSEC-signed parent can cause Unbound to send more upstream packets per client query than the configured 'max-global-quota'. This effectively bypasses a security configuration that limits upstream amplification traffic.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 18:56 UTC
CWE
  • CWE-406 - Insufficient Control of Network Message Volume (Network Amplification)
Assigner
References
Impacted products
Vendor Product Version CPE status
NLnet Labs Unbound Affected: 1.22.0 , < 1.25.2 (semver)
guessed Create a notification for this product.
Date Public
2026-07-22 00:00
Credits
Kunjie Shang (University of Science and Technology of China)
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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