CVE-2023-42452: Mastodon vulnerable to Stored XSS through the translation feature

Published Sep 19, 2023
·
Updated

Mastodon is a free, open-source social network server based on ActivityPub. In versions on the 4.x branch prior to versions 4.0.10, 4.2.8, and 4.2.0-rc2, under certain conditions, attackers can abuse the translation feature to bypass the server-side HTML sanitization, allowing unescaped HTML to execute in the browser. The impact is limited thanks to Mastodon's strict Content Security Policy, blocking inline scripts, etc. However a CSP bypass or loophole could be exploited to execute malicious XSS. Furthermore, it requires user interaction, as this can only occur upon clicking the “Translate” button on a malicious post. Versions 4.0.10, 4.2.8, and 4.2.0-rc2 contain a patch for this issue.

Affected Software

6 affected components
Joinmastodon Mastodon>=4.0.0<4.0.10
Joinmastodon Mastodon>=4.1.0<4.1.8
Joinmastodon Mastodon=4.2.0-beta1
Joinmastodon Mastodon=4.2.0-beta2
Joinmastodon Mastodon=4.2.0-beta3
Joinmastodon Mastodon=4.2.0-rc1

Event History

Sep 19, 2023
CVE Published
via MITRE·03:58 PM
Data Sourced
via MITRE·03:58 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2023-42452?

CVE-2023-42452 is a vulnerability in the Mastodon social network server that allows attackers to bypass server-side HTML sanitization.

2

What is the severity of CVE-2023-42452?

The severity of CVE-2023-42452 is medium with a score of 5.4.

3

How does CVE-2023-42452 affect Mastodon?

CVE-2023-42452 affects Mastodon versions on the 4.x branch prior to versions 4.0.10, 4.2.8, and 4.2.0-rc2.

4

How can attackers exploit CVE-2023-42452?

Attackers can abuse the translation feature in affected versions of Mastodon to bypass HTML sanitization and execute unescaped HTML.

5

How can I fix CVE-2023-42452?

To fix CVE-2023-42452, it is recommended to update Mastodon to versions 4.0.10, 4.2.8, or 4.2.0-rc2 or later.

Contact

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