CVE-2026-33195Network attack vector

Arbitrary file access via unchecked blob keys

Published Mar 23, 2026 · Updated Mar 23, 2026

Path traversal in Rails Active Storage DiskService allows attackers to read, write, or delete arbitrary server files through crafted blob keys. DiskService#path_for joins each blob key to the storage root without resolving the result and verifying that it remains inside that root. Exploitation requires an application to pass attacker-influenced input as a custom blob key while using the local Disk service; generated trusted keys and cloud services do not expose this path.

CVSS severity9.8
Critical
EPSS probability0.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Rails Active Storage DiskService allows attackers to read, write, or delete arbitrary server files through crafted blob keys. DiskService#path_for joins each blob key to the storage root without resolving the result and verifying that it remains inside that root. Exploitation requires an application to pass attacker-influenced input as a custom blob key while using the local Disk service; generated trusted keys and cloud services do not expose this path.

The record

CVE
CVE-2026-33195
Published
Mar 23, 2026
Updated
Mar 23, 2026
Vendor
Rails
Product
Active Storage
Classifications
CWE-22, T1005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 7.2.3.1
  2. Affected versionversion=>= 8.0.0.beta1, < 8.0.4.1
  3. Affected versionversion=>= 8.1.0.beta1, < 8.1.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Rails · Active Storageversion=< 7.2.3.1; version=>= 8.0.0.beta1, < 8.0.4.1; version=>= 8.1.0.beta1, < 8.1.2.1

Published CVSS scores

8.0GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.1Red HatCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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