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Back to active CVEs
High · CVSS 7.5CVE-2026-84851

Uncontrolled recursion in the Ion reader in Amazon Ion-C before 1.1.6CVE-2026-84851

Answer in brief

CVE-2026-84851 records a High severity (CVSS 7.5) vulnerability in Uncontrolled recursion in the Ion reader in Amazon Ion-C before 1.1.6. The current sources do not mark it as known exploited. The current feed maps Amazon/ion-c (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 2, 2026Updated Sep 3, 2026Source checked Oct 18, 2026First seen by HOL Sep 2, 2026Material review Sep 3, 2026
Upstream Advisory

Key facts

Risk
High · CVSS 7.5
Exploitation
Not marked as known exploited
Affected software
1 mapped package or product
Fix availability
Available

Why this deserves its current priority

CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Amazon/ion-c (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Amazon/ion-cgeneric>=0 <1.1.61.1.6

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Amazon/ion-c.
  2. 2Review the reported fix. Update Amazon/ion-c to 1.1.6 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Sep 2, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Sep 3, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Sep 2, 2026

Sources and claim methodology

  • Source referenceaws.amazon.com
  • GitHub security advisorygithub.com
  • GitHub security advisorygithub.com
Upstream source description

An uncontrolled recursion issue exists in Amazon Ion-C versions before 1.1.6 that might allow a remote unauthenticated actor to craft Ion data that exhausts the native call stack and crashes the application using the library, resulting in a denial of service.

Quoted source text, attributed separately from HOL analysis.

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  • nemoTyrant manong func.php arr2sql sql injectionSame generic ecosystem
  • phpMyFAQ 4.2.0-alpha before 4.2.0-beta Missing Authorization via deleteGroup APISame generic ecosystem
  • phpMyFAQ 4.2.0-alpha.2 before 4.2.0-beta 2FA Brute-Force via remove-twofactor EndpointSame generic ecosystem

Record context

Vulnerability class
Missing Auth
EPSS
Not reported
CWE IDs
CWE-674
Source
CVE List V5
Source checked
Oct 18, 2026
References
3 linked sources
Open source record