CVE-2023-36459

Mastodon vulnerable to Cross-site Scripting through oEmbed preview cards

Description

Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 1.3 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker using carefully crafted oEmbed data can bypass the HTML sanitization performed by Mastodon and include arbitrary HTML in oEmbed preview cards. This introduces a vector for cross-site scripting (XSS) payloads that can be rendered in the user's browser when a preview card for a malicious link is clicked through. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.

Category

9.3
CVSS
Severity: Critical
CVSS 3.1 •
EPSS 0.12%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: mastodon mastodon
Published at:
Updated at:

References

Link Tags
https://github.com/mastodon/mastodon/security/advisories/GHSA-ccm4-vgcc-73hp third party advisory
https://github.com/mastodon/mastodon/commit/6d8e0fae3e96f3cf4febe03fa7fcf5b95ff761b2 third party advisory patch
https://github.com/mastodon/mastodon/releases/tag/v3.5.9 third party advisory
https://github.com/mastodon/mastodon/releases/tag/v4.0.5 third party advisory
https://github.com/mastodon/mastodon/releases/tag/v4.1.3 third party advisory
http://www.openwall.com/lists/oss-security/2023/07/06/5 mailing list

Frequently Asked Questions

What is the severity of CVE-2023-36459?
CVE-2023-36459 has been scored as a critical severity vulnerability.
How to fix CVE-2023-36459?
To fix CVE-2023-36459, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-36459 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-36459 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-36459?
CVE-2023-36459 affects mastodon mastodon.
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