CVE-2021-32764

HIGH

Discourse < 2.7.5 - Cross-Site Scripting via YouTube Onebox Parsing

Title source: llm
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 8.1
EPSS 0.0024
EPSS Percentile 46.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Details

CWE
CWE-79
Status published
Products (2)
discourse/discourse 2.8.0 beta1
discourse/discourse < 2.7.5
Published Jul 15, 2021
Tracked Since Feb 18, 2026