CVE-2026-45780Network attack vector

Private event invitee disclosure via missing authorization

Published Jul 9, 2026 · Updated Jul 9, 2026

Information disclosure in Discourse allows remote attackers who can view a topic to read its private event invitee details. EventSerializer returned raw invited groups, sample invitees, and attendance statistics without first checking whether the viewer could see invitee details. The exposed data is limited to private-event invitation and attendance metadata; no content modification or service interruption is reported.

CVSS severity5.3
Medium
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Discourse allows remote attackers who can view a topic to read its private event invitee details. EventSerializer returned raw invited groups, sample invitees, and attendance statistics without first checking whether the viewer could see invitee details. The exposed data is limited to private-event invitation and attendance metadata; no content modification or service interruption is reported.

The record

CVE
CVE-2026-45780
Published
Jul 9, 2026
Updated
Jul 9, 2026
Vendor
Discourse
Product
Discourse
Classifications
CWE-200, T1213
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 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=>= 2026.1.0-latest, < 2026.1.5
  2. Affected versionversion=>= 2026.4.0-latest, < 2026.4.2
  3. Affected versionversion=>= 2026.5.0-latest, < 2026.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Discourse · Discourseversion=>= 2026.1.0-latest, < 2026.1.5; version=>= 2026.4.0-latest, < 2026.4.2; version=>= 2026.5.0-latest, < 2026.5.1

Published CVSS scores

5.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
4.3NIST NVDCVSS: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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
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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