7.3
HIGH CVSS 3.1
CVE-2026-53963
Discourse: Stored-XSS in 2FA delete confirmation modal
Description

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.

INFO

Published Date :

July 9, 2026, 10:17 p.m.

Last Modified :

July 9, 2026, 10:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-53963 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update Discourse to patched versions to fix stored XSS vulnerability.
  • Update Discourse to version 2026.6.0 or later.
  • Apply relevant patches if updating is not possible.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-53963 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-53963 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-53963 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-53963 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 09, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'discourse', 'product': 'discourse', 'versions': [{'status': 'affected', 'version': '>= 2026.1.0-latest, < 2026.1.5'}, {'status': 'affected', 'version': '>= 2026.4.0-latest, < 2026.4.2'}, {'status': 'affected', 'version': '>= 2026.5.0-latest, < 2026.5.1'}]}]
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
    Added CWE CWE-79
    Added Reference https://github.com/discourse/discourse/commit/40de62cddadc65c328a1028ab999f3fa94adbfed
    Added Reference https://github.com/discourse/discourse/commit/529e17d4d570a48972e7cf64720e5dd1fdf23ca8
    Added Reference https://github.com/discourse/discourse/commit/d92973e51a46cf6dd20c71e6068e6769b67eea5b
    Added Reference https://github.com/discourse/discourse/commit/daea5214d833eacbdd3b1a78d99eb14e9cabd915
    Added Reference https://github.com/discourse/discourse/releases/tag/v2026.1.5
    Added Reference https://github.com/discourse/discourse/releases/tag/v2026.4.2
    Added Reference https://github.com/discourse/discourse/releases/tag/v2026.5.1
    Added Reference https://github.com/discourse/discourse/releases/tag/v2026.6.0
    Added Reference https://github.com/discourse/discourse/security/advisories/GHSA-wg5x-7f23-m3r5
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.