CVE-2024-28242Network attack vector

Secret-category disclosure via globally compiled background CSS

Published Mar 15, 2024 · Updated Aug 26, 2024

Information disclosure in Discourse 3.2.0 and earlier allows remote attackers to discover secret categories with custom backgrounds. The server-side Stylesheet::Importer#category_backgrounds method queries every category with an uploaded background and emits its slug and background URL into globally compiled CSS without filtering by the requester's category visibility. The leak requires a secret category to have a background; beta and tests-passed 3.3.0.beta1 and earlier are also affected, and exposure is limited to category existence and background metadata.

CVSS severity5.3
Medium
EPSS probability0.49%
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 3.2.0 and earlier allows remote attackers to discover secret categories with custom backgrounds. The server-side Stylesheet::Importer#category_backgrounds method queries every category with an uploaded background and emits its slug and background URL into globally compiled CSS without filtering by the requester's category visibility. The leak requires a secret category to have a background; beta and tests-passed 3.3.0.beta1 and earlier are also affected, and exposure is limited to category existence and background metadata.

The record

CVE
CVE-2024-28242
Published
Mar 15, 2024
Updated
Aug 26, 2024
Vendor
Discourse
Product
Discourse
Classifications
CWE-200, CWE-285
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 15, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2024Record 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=0 <=3.2.0
  2. Affected versionversion=beta <= 3.3.0.beta1
  3. Affected versionversion=beta <=3.3.0.beta1
  4. Affected versionversion=stable <= 3.2.0
  5. Affected versionversion=tests-passed <= 3.3.0.beta1
  6. Affected versionversion=tests-passed <=3.3.0.beta1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Discourse · Discourseversion=0 <=3.2.0; version=beta <= 3.3.0.beta1; version=beta <=3.3.0.beta1; version=stable <= 3.2.0; version=tests-passed <= 3.3.0.beta1; version=tests-passed <=3.3.0.beta1

Published CVSS scores

5.3GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-285Improper Authorization

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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