Vulnerability in Amazon Ion Python (CVE-2026-104020)
Summary
Vulnerability in Amazon Ion Python (CVE-2026-104020). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
Bulletin ID: 2026-122-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/01/2026 13:30 PM PDT Description: Amazon Ion Python is an open-source Python implementation of the Amazon Ion data notation. We identified CVE-2026-104020, an issue in the Ion reader in Amazon Ion Python before version 0.15.0 where a crafted, deeply nested Ion value could cause the application to raise an error or crash, resulting in a denial of service. Impacted versions: < 0.15.0 Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.
Source: AWS Security Bulletins NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-104020 has been found in Amazon Ion Python.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Amazon Ion Python CVE-2026-104020" on the vendor's site.
CVE-2026-104020 (Amazon Ion Python) — CWE-674 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-674) exists in Amazon Ion Python.
Check the vendor advisory for the affected versions of Amazon Ion Python.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Amazon Ion Python を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- AWS aws.amazon.com
- web aws.amazon.com
- web github.com
- web github.com