Uncontrolled recursion in the Ion reader in Amazon Ion Python before 0.15.0 might allow a remote unauthenticated actor to crash the application using the library, resulting in a denial of service, via a crafted, deeply nested Ion value.
To remediate this issue, users should upgrade to version 0.15.0 or later.
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recursion in the Ion reader in Amazon Ion Python","CVE":"CVE-2026-104020","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"104020","Ordinal":"1","NoteData":"Uncontrolled recursion in the Ion reader in Amazon Ion Python before 0.15.0 might allow a remote unauthenticated actor to crash the application using the library, resulting in a denial of service, via a crafted, deeply nested Ion value.\n\n\n\nTo remediate this issue, users should upgrade to version 0.15.0 or later.","Type":"Description","Title":"Uncontrolled recursion in the Ion reader in Amazon Ion Python"}]}}}