CVE-2026-104020

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

Not scored by EPSS

EPSS percentile

Not scored by EPSS

NVD base score

8.7 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Received. NVD last modified this record on 2026-10-01.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-10-01 20:36Z1 HR AGO

Last updated

2026-10-01 21:07Z1 HR AGO

Reserved

2026-10-01

Assigning CNA

AMZN

Record state

PUBLISHED

Severity

High (CVSS 8.7)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Weaknesses

• CWE-674Uncontrolled RecursionClass

Data version

5.2

Document digest

5fc8f50620f9b514a7b801f49ebd95579c0762be069f47dc4965f3a4fca5ded5

• github.comhttps://github.com/amazon-ion/ion-python/releases/tag/v0.15.0patch
• aws.amazon.comhttps://aws.amazon.com/security/security-bulletins/2026-122-aws/vendor-advisory
• github.comhttps://github.com/amazon-ion/ion-python/security/advisories/GHSA-93q6-f8hx-vv7fthird-party-advisory