CVE-2026-53769Public exploitNetwork attack vectorHinoki check available

Protected attachment overwrite via missing upload authorization

Published Sep 4, 2026 · Updated Sep 4, 2026

Incorrect authorization in Avo 2.28.0 through 3.31.x allows remote authenticated users to add or replace protected attachments. Avo::AttachmentsController#create creates an ActiveStorage blob and attaches it without invoking the field upload or record update policy. Exposure requires a restricted user who can reach Avo in a multi-role deployment; successful requests control attachment content, filename, and content type.

CVSS severity6.5
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect authorization in Avo 2.28.0 through 3.31.x allows remote authenticated users to add or replace protected attachments. Avo::AttachmentsController#create creates an ActiveStorage blob and attaches it without invoking the field upload or record update policy. Exposure requires a restricted user who can reach Avo in a multi-role deployment; successful requests control attachment content, filename, and content type.

The record

CVE
CVE-2026-53769
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
Avo
Product
Avo
Classifications
CWE-862, CWE-863, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=>= 2.28.0, < 3.32.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Avo · Avoversion=>= 2.28.0, < 3.32.0

Published CVSS scores

6.5Avo GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
CWE-863Incorrect Authorization
T1565.001Data Manipulation: Stored Data Manipulation

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo