CVE-2026-53963

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, a malicious second factor name on an attacker-controlled account was not escaped in the delete confirmation dialog, allowing stored cross-site scripting when an administrator impersonated that account. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/commit/40de62cddadc65c328a1028ab999f3fa94adbfed	Patch
https://github.com/discourse/discourse/commit/529e17d4d570a48972e7cf64720e5dd1fdf23ca8	Patch
https://github.com/discourse/discourse/commit/d92973e51a46cf6dd20c71e6068e6769b67eea5b	Patch
https://github.com/discourse/discourse/commit/daea5214d833eacbdd3b1a78d99eb14e9cabd915	Patch
https://github.com/discourse/discourse/releases/tag/v2026.1.5	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.4.2	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.5.1	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.6.0	Release Notes
https://github.com/discourse/discourse/security/advisories/GHSA-wg5x-7f23-m3r5	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.6.0::::latest:::

History

No history.

Information

Published : 2026-07-09 22:17

Updated : 2026-07-14 02:16

NVD link : CVE-2026-53963

Mitre link : CVE-2026-53963

CVE.ORG link : CVE-2026-53963

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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