CVE-2024-37903: mastodon Auth Bypass — Fix

Description

Mastodon is a self-hosted, federated microblogging platform. Starting in version 2.6.0 and prior to versions 4.1.18 and 4.2.10, by crafting specific activities, an attacker can extend the audience of a post they do not own to other Mastodon users on a target server, thus gaining access to the contents of a post not intended for them. Versions 4.1.18 and 4.2.10 contain a patch for this issue.

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CVSS v3.1 Score

8.2

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Weakness Type (CWE)

CWE-862 Missing Authorization

Affected Products

Vendor	Product	Versions
joinmastodon	mastodon	2.6.0 — 4.1.18
joinmastodon	mastodon	4.2.0 — 4.2.10

References

Advisories & Patches

https://github.com/mastodon/mastodon/commit/a1c7aae28aecf06659c5b18cfa131b37cd1512a3 https://github.com/mastodon/mastodon/commit/d4bf22b632ea8b1174375c4966a6768ab66393b6 https://github.com/mastodon/mastodon/security/advisories/GHSA-xjvf-fm67-4qc3 https://github.com/mastodon/mastodon/commit/a1c7aae28aecf06659c5b18cfa131b37cd1512a3 https://github.com/mastodon/mastodon/commit/d4bf22b632ea8b1174375c4966a6768ab66393b6 https://github.com/mastodon/mastodon/security/advisories/GHSA-xjvf-fm67-4qc3

Other References

https://github.com/mastodon/mastodon/releases/tag/v4.1.18 https://github.com/mastodon/mastodon/releases/tag/v4.2.10 https://github.com/mastodon/mastodon/releases/tag/v4.1.18 https://github.com/mastodon/mastodon/releases/tag/v4.2.10

Frequently Asked Questions

What is CVE-2024-37903? +

Mastodon is a self-hosted, federated microblogging platform. Starting in version 2.6.0 and prior to versions 4.1.18 and 4.2.10, by crafting specific activities, an attacker can extend the audience of a post they do not own to other Mastodon users on a target server, thus gaining access to the contents of a post not intended for them. Versions 4.1.18 and 4.2.10 contain a patch for this issue. It has a CVSS v3.1 base score of 8.2 (HIGH).

How severe is CVE-2024-37903? +

CVE-2024-37903 has a CVSS v3.1 score of 8.2 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-37903? +

CVE-2024-37903 affects products from joinmastodon, specifically: mastodon. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-37903? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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