CVE-2026-104020CWE-674

CVE-2026-104020

High · published October 2, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
37.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
8.7 · 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
EPSS
0.00441 · 37.3th percentile
Weakness
CWE-674 · Uncontrolled Recursion
Published
2026-10-02T01:17Z
References (3)
https://aws.amazon.com/security/security-bulletins/2026-122-aws/ · ff89ba41-3aa1-4d27-914a-91399e9639e5https://github.com/amazon-ion/ion-python/releases/tag/v0.15.0 · ff89ba41-3aa1-4d27-914a-91399e9639e5https://github.com/amazon-ion/ion-python/security/advisories/GHSA-93q6-f8hx-vv7f · ff89ba41-3aa1-4d27-914a-91399e9639e5
EPSS history
Timeline
  • 03 OCT 03:41Z
    EPSS moved — → 0%
    epss
  • 01 OCT 20:36Z
    Uncontrolled recursion in the Ion reader in Amazon Ion Python
    cvelistv5