CVE-2026-1519 (GCVE-0-2026-1519)

Vulnerability from cvelistv5 – Published: 2026-03-25 13:25 – Updated: 2026-03-25 14:55
VLAI?
Title
Excessive NSEC3 iterations cause high CPU load during insecure delegation validation
Summary
If a BIND resolver is performing DNSSEC validation and encounters a maliciously crafted zone, the resolver may consume excessive CPU. Authoritative-only servers are generally unaffected, although there are circumstances where authoritative servers may make recursive queries (see: https://kb.isc.org/docs/why-does-my-authoritative-server-make-recursive-queries). This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.46, 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.46-S1, and 9.20.9-S1 through 9.20.20-S1.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-606 - Unchecked Input for Loop Condition
Assigner
isc
References
Impacted products
Vendor Product Version
ISC BIND 9 Affected: 9.11.0 , ≤ 9.16.50 (custom)
Affected: 9.18.0 , ≤ 9.18.46 (custom)
Affected: 9.20.0 , ≤ 9.20.20 (custom)
Affected: 9.21.0 , ≤ 9.21.19 (custom)
Affected: 9.11.3-S1 , ≤ 9.16.50-S1 (custom)
Affected: 9.18.11-S1 , ≤ 9.18.46-S1 (custom)
Affected: 9.20.9-S1 , ≤ 9.20.20-S1 (custom)
Create a notification for this product.
Date Public ?
2026-03-25 00:00
Credits
ISC would like to thank Samy Medjahed/Ap4sh for bringing this vulnerability to our attention.
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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