Medium severity · published Feb 4, 2025
CVE-2024-56328
HTMLi(XSS without CSP) via Onebox urls in Discourse
6.1
CVSS
0.4%
EPSS
No
On KEV
Description
Discourse is an open source platform for community discussion. An attacker can execute arbitrary JavaScript on users' browsers by posting a maliciously crafted onebox url. This issue only affects sites with CSP disabled. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should enable CSP, disable inline Oneboxes globally, or allow specific domains for Oneboxing.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
discourse · discourse
stable: <= 3.3.3; beta: <= 3.4.0.beta3; tests-passed: <= 3.4.0.beta3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2024-56328
CVE.org
https://www.cve.org/CVERecord?id=CVE-2024-56328
Third Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-j855-mhxj-x6vg
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