CVE-2026-33173

EUVD-2026-14626
Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, `DirectUploadsController` accepts arbitrary metadata from the client and persists it on the blob. Because internal flags like `identified` and `analyzed` are stored in the same metadata hash, a direct-upload client can set these flags to skip MIME detection and analysis. This allows an attacker to upload arbitrary content while claiming a safe `content_type`, bypassing any validations that rely on Active Storage's automatic content type identification. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 31.8%
Affected Products (NVD)
VendorProductVersion
rubyonrailsrails
𝑥
< 7.2.3.1
rubyonrailsrails
8.0.0 ≤
𝑥
< 8.0.4.1
rubyonrailsrails
8.1.0 ≤
𝑥
< 8.1.2.1
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
rails
bookworm
no-dsa
bookworm (security)
vulnerable
bullseye
postponed
bullseye (security)
vulnerable
forky
2:7.2.3.2+dfsg-2
fixed
sid
2:7.2.3.2+dfsg-2
fixed
trixie
no-dsa
trixie (security)
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
rails
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
ignored
resolute
needs-triage
xenial
ignored