CVE-2021-39195: Server-Side Request Forgery vulnerability in misskey

Published Sep 7, 2021
·
Updated

Misskey is an open source, decentralized microblogging platform. In affected versions a Server-Side Request Forgery vulnerability exists in "Upload from URL" and remote attachment handling. This could result in the disclosure of non-public information within the internal network. This has been fixed in 12.90.0. However, if you are using a proxy, you will need to take additional measures. As a workaround this exploit may be avoided by appropriately restricting access to private networks from the host where the application is running.

Affected Software

1 affected component
Misskey Misskey<12.90.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade misskey to a version that resolves this vulnerability.

    Fixed in 12.90.0
  2. Compensating control

    As a workaround, restrict access to private networks from the host where the Misskey application is running to avoid the SSRF conditions.

  3. Compensating control

    If using a proxy with Misskey, take additional measures (per proxy configuration) to prevent SSRF from reaching private/internal networks.

Event History

Sep 7, 2021
CVE Published
via MITRE·07:00 PM
Data Sourced
via MITRE·07:00 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·07:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-39195?

CVE-2021-39195 is a Server-Side Request Forgery vulnerability found in the Misskey microblogging platform.

2

What is the severity of CVE-2021-39195?

CVE-2021-39195 has a severity rating of 6.5, which is considered high.

3

How does CVE-2021-39195 affect Misskey?

CVE-2021-39195 affects Misskey versions up to 12.90.0.

4

What is the risk of CVE-2021-39195?

CVE-2021-39195 could lead to the disclosure of non-public information within the internal network.

5

How can CVE-2021-39195 be fixed?

To fix CVE-2021-39195, users should update to the latest version of Misskey.

Contact

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