CVE-2026-30889Network attack vector

Moderator post metadata disclosure via missing authorization

Published Mar 20, 2026 · Updated Mar 20, 2026

Missing authorization in Discourse allows remote authenticated users with moderator access to read restricted post metadata over the network. The discourse-user-notes component returns metadata for posts the requesting moderator cannot otherwise view because its authorization checks do not enforce post visibility; the exact handler and omitted check are undisclosed. Affected builds include 2026.1 versions before 2026.1.2, 2026.2 versions before 2026.2.1, and the cataloged 2026.3.0-latest.1 build; the reported consequence is metadata disclosure only.

CVSS severity5.3
Medium
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Discourse allows remote authenticated users with moderator access to read restricted post metadata over the network. The discourse-user-notes component returns metadata for posts the requesting moderator cannot otherwise view because its authorization checks do not enforce post visibility; the exact handler and omitted check are undisclosed. Affected builds include 2026.1 versions before 2026.1.2, 2026.2 versions before 2026.2.1, and the cataloged 2026.3.0-latest.1 build; the reported consequence is metadata disclosure only.

The record

CVE
CVE-2026-30889
Published
Mar 20, 2026
Updated
Mar 20, 2026
Vendor
Discourse
Product
Discourse
Classifications
CWE-862, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 20, 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=>= 2026.1.0-latest, < 2026.1.2
  2. Affected versionversion=>= 2026.2.0-latest, < 2026.2.1
  3. Affected versionversion== 2026.3.0-latest.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=>= 2026.1.0-latest, < 2026.1.2; version=>= 2026.2.0-latest, < 2026.2.1; version== 2026.3.0-latest.1

Published CVSS scores

5.3GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
4.9NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/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-862Missing Authorization
T1213Data from Information Repositories

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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