How severe is CVE-2023-52139?

CVE-2023-52139 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-52139 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-52139?

CVE-2023-52139 affects Misskey. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-52139?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-52139 published?

CVE-2023-52139 was published on 2023-12-29 and last updated on 2026-06-17.

CVE-2023-52139

CVE-2023-52139 is a critical-severity vulnerability in Misskey with a CVSS 3.x base score of 9.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-285.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-285
Affected product: Misskey
Published: 2023-12-29
Last modified: 2026-06-17

Description

Misskey is an open source, decentralized social media platform. Third-party applications may be able to access some endpoints or Websocket APIs that are incorrectly specified as [kind](https://github.com/misskey-dev/misskey/blob/406b4bdbe79b5b0b68fcdcb3c4b6e419460a0258/packages/backend/src/server/api/endpoints.ts#L811) or [secure](https://github.com/misskey-dev/misskey/blob/406b4bdbe79b5b0b68fcdcb3c4b6e419460a0258/packages/backend/src/server/api/endpoints.ts#L805) without the user's permission and perform operations such as reading or adding non-public content. As a result, if the user who authenticated the application is an administrator, confidential information such as object storage secret keys and SMTP server passwords will be leaked, and general users can also create invitation codes without permission and leak non-public user information. This is patched in version [2023.12.1](https://github.com/misskey-dev/misskey/commit/c96bc36fedc804dc840ea791a9355d7df0748e64).

Frequently asked questions

What is CVE-2023-52139?: Misskey is an open source, decentralized social media platform. Third-party applications may be able to access some endpoints or Websocket APIs that are incorrectly specified as [kind](https://github.com/misskey-dev/misskey/blob/406b4bdbe79b5b0b68fcdcb3c4b6e419460a0258/packages/backend/src/server/api/endpoints.ts#L811) or [secure](https://github.com/misskey-dev/misskey/blob/406b4bdbe79b5b0b68fcdcb3c4b6e419460a0258/packages/backend/src/server/api/endpoints.ts#L805) without the user's permission and perform operations such as reading or adding non-public content. As a result, if the user who authenticated the application is an administrator, confidential information such as object storage secret keys and SMTP server passwords will be leaked, and general users can also create invitation codes without permission and leak non-public user information. This is patched in version [2023.12.1](https://github.com/misskey-dev/misskey/commit/c96bc36fedc804dc840ea791a9355d7df0748e64).
How severe is CVE-2023-52139?: CVE-2023-52139 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-52139 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-52139?: CVE-2023-52139 affects Misskey. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-52139?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-52139 published?: CVE-2023-52139 was published on 2023-12-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:misskey:misskey:*:*:*:*:*:*:*:*

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