Allocation of Resources Without Limits or Throttling Affecting unbound-debuginfo package, versions <0:1.17.1-1.amzn2023.0.15


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.48% (39th percentile)

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  • Snyk IDSNYK-AMZN2023-UNBOUNDDEBUGINFO-20248516
  • published29 Sept 2026
  • disclosed16 Sept 2026

Introduced: 16 Sep 2026

CVE-2026-85501  (opens in a new tab)
CWE-770  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 unbound-debuginfo to version 0:1.17.1-1.amzn2023.0.15 or higher.
This issue was patched in ALAS2023-2026-3127.

NVD Description

Note: Versions mentioned in the description apply only to the upstream unbound-debuginfo package and not the unbound-debuginfo package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

Novel vulnerabilities to launch algorithmic complexity attacks on DNSSEC have been researched under the term 'ReTrap'. These result in degradation of service when malicious zones are used to serve the algorithmic complexity vulnerabilities. NLnet Labs Unbound up to and including 1.26.0 is vulnerable to some of them. TagTrap, where the triple(Zone, Algo, KeyTag) matching mechanism introduces a significant attack vector when resolvers handle malicious responses containing numerous mismatched DNSKEY, RRSIG, and DS record. DelegationTrap, where constructing the chain-of-trust requires iterative validation of DNSKEY and DS records from the root zone downward. For deeply nested domains, this results in significant computational overhead. NsecTrap, where responses with excessive invalid NSEC records compel the resolver to validate each one. AdditionalTrap, where Unbound by default would try to DNSSEC validate the ADDITIONAL section as well. This can be exploited to waste validation resources by malicious users.

CVSS Base Scores

version 3.1