Vulnerability · Published Sep 2, 2026 · Assigned by AMZN
CVE-2026-84851Uncontrolled recursion in the Ion reader in Amazon Ion-C before 1.1.6
High 7.5
In plain English
A high-severity security flaw in ion-c from Amazon. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.6%top 50.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/amazon-ion/ion-c/releases/tag/v1.1.6 release-notes, patch
- https://aws.amazon.com/security/security-bulletins/2026-094-aws/ vendor-advisory
- https://github.com/amazon-ion/ion-c/security/advisories/GHSA-9gfg-hgj4-gh44 release-notes