What is CVE-2026-122006?

CVE-2026-122006 is a critical-severity vulnerability in Rubyonrails Active Storage, classified under Initialization of a Resource with an Insecure Default. CVSS score: 9.8/10. Published 2026-11-04.

How severe is CVE-2026-122006?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-122006 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

RCE in Rubyonrails Active Storage

CVE-2026-122006

The activestorage gem before 8.1.4.1 for Ruby on Rails, when ImageMagick attachment processing occurs, can allow server read and write operations (e.g., reading secret_key_base) because the ImageMagick analyzer runs when a file is attached, and there is not an ImageMagick security policy to block unintended functionality.

Published 2026-11-04 · last modified 2026-11-05.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Rubyonrails Active Storage

Weakness classification (CWE)

CWE-1188 — Initialization of a Resource with an Insecure Default

Public proof-of-concept exploits

charlie-goldenowl/cve-2026-122006-check

References

Frequently asked questions

What is CVE-2026-122006?: CVE-2026-122006 is a critical-severity vulnerability in Rubyonrails Active Storage, classified under Initialization of a Resource with an Insecure Default. CVSS score: 9.8/10. Published 2026-11-04.
How severe is CVE-2026-122006?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-122006 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.