CVE-2025-58055Network attack vector

Restricted-topic disclosure via unchecked suggestion topic ID

Published Oct 1, 2025 · Updated Oct 23, 2025

Improper access control in Discourse before 3.5.1 allows remote authenticated users to read restricted topic data via AI suggestions. The discourse-ai assistant controller accepted a user-controlled topic_id for title, category, and tag suggestions without calling Guardian to verify topic visibility. Access to an enabled AI helper is required; the resulting model output discloses topic information but does not modify topics or interrupt service.

CVSS severity4.3
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Discourse before 3.5.1 allows remote authenticated users to read restricted topic data via AI suggestions. The discourse-ai assistant controller accepted a user-controlled topic_id for title, category, and tag suggestions without calling Guardian to verify topic visibility. Access to an enabled AI helper is required; the resulting model output discloses topic information but does not modify topics or interrupt service.

The record

CVE
CVE-2025-58055
Published
Oct 1, 2025
Updated
Oct 23, 2025
Vendor
Discourse
Product
Discourse
Classifications
CWE-639, CWE-284, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 23, 2025Record 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=< 3.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=< 3.5.1

Published CVSS scores

4.3GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
CWE-284Improper Access Control
T1190Exploit Public-Facing Application

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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