CVE-2026-104020

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-122-aws/
https://github.com/amazon-ion/ion-python/releases/tag/v0.15.0
https://github.com/amazon-ion/ion-python/security/advisories/GHSA-93q6-f8hx-vv7f

Configurations

No configuration.

History

01 Oct 2026, 22:17

Type	Values Removed	Values Added
References		() https://github.com/amazon-ion/ion-python/security/advisories/GHSA-93q6-f8hx-vv7f -

01 Oct 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-01 21:17

Updated : 2026-10-02 19:16

NVD link : CVE-2026-104020

Mitre link : CVE-2026-104020

CVE.ORG link : CVE-2026-104020

JSON object : View

Products Affected

No product.

CWE

CWE-674

Uncontrolled Recursion

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