CVE-2026-27021Network attack vector

Unauthenticated poll voter disclosure via missing visibility check

Published Feb 26, 2026 · Updated Feb 26, 2026

Information disclosure in Discourse before 2025.12.2, 2026.1.1, or 2026.2.0 allows remote attackers to read poll voter details. The poll plugin's voters endpoint returns voter details without checking whether the requester can view the poll's containing post. No authentication or user interaction is required, and the consequence is limited to voter details from polls in inaccessible posts.

CVSS severity6.9
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

Information disclosure in Discourse before 2025.12.2, 2026.1.1, or 2026.2.0 allows remote attackers to read poll voter details. The poll plugin's voters endpoint returns voter details without checking whether the requester can view the poll's containing post. No authentication or user interaction is required, and the consequence is limited to voter details from polls in inaccessible posts.

The record

CVE
CVE-2026-27021
Published
Feb 26, 2026
Updated
Feb 26, 2026
Vendor
Discourse
Product
Discourse
Classifications
CWE-862, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 26, 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=< 2025.12.2
  2. Affected versionversion=>= 2026.1.0-latest, < 2026.1.1
  3. Affected versionversion=>= 2026.2.0-latest, < 2026.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Discourse · Discourseversion=< 2025.12.2; version=>= 2026.1.0-latest, < 2026.1.1; version=>= 2026.2.0-latest, < 2026.2.0

Published CVSS scores

6.9GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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-862Missing Authorization
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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