Medium severity · published Jul 15, 2021
CVE-2021-32764
Discourse is an open-source discussion platform
5.4
CVSS
0.5%
EPSS
No
On KEV
Description
Discourse is an open-source discussion platform. In Discourse versions 2.7.5 and prior, parsing and rendering of YouTube Oneboxes can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse's default Content Security Policy. The issue is patched in `stable` version 2.7.6, `beta` version 2.8.0.beta3, and `tests-passed` version 2.8.0.beta3. As a workaround, ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
Discourse · Discourse
through 2.7.5; 2.8.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-32764
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-32764
Third Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-9x4c-29xg-56hw
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