Vulnerability · CVE-2025-46340
Misskey is an open source, federated social media platform.
Published May 5, 2025 · corrected/updated May 5, 2025 · misskey-dev misskey · evidence confidence high
Misskey is an open source, federated social media platform. Starting in version 12.0.0 and prior to version 2025.4.1, due to an oversight in the validation performed in and , it is possible for an attacker to inject arbitrary CSS into the component. falls back to returning the original URL if it's using a protocol that is likely to not be understood by Misskey, IE something other than or . This both can de-anonymize users and_allow further attacks in the client. Additionally, doesn't escape CSS when applying a property, allowing an attacker to craft a URL that applies arbitrary styles to the p
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2025-46340 is a high public vulnerability record for misskey-dev misskey. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether misskey-dev misskey is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: misskey-dev misskey 12.0.0, < 2025.4.1 (12.0.0, < 2025.4.1). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 7.2 (technical impact); EPSS 25.0% (30-day exploitation probability). It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: euvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
Affected version ranges suggest a fixed boundary. Verify against the vendor advisory for your release.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 5, 2025 · EUVD
Detected
Misskey is an open source, federated social media platform. Starting in version 12.0.0 and prior to version 2025.4.1, due to an oversight in the validation performed in and , it is possible for an attacker to inject arbitrary CSS into the component. falls back to returning the original URL if it's using a protocol that is likely to not be understood by Misskey, IE something other than or . This bo
May 5, 2025 · EUVD
Updated
Misskey is an open source, federated social media platform. Starting in version 12.0.0 and prior to version 2025.4.1, due to an oversight in the validation performed in and , it is possible for an attacker to inject arbitrary CSS into the component. falls back to returning the original URL if it's using a protocol that is likely to not be understood by Misskey, IE something other than or . This bo
Affected
- vendor misskey-dev misskey 12.0.0, < 2025.4.112.0.0, < 2025.4.1
Sources
- EUVDVulnerability recordEUVD-2025-13505
Misskey is an open source, federated social media platform. Starting in version 12.0.0 and prior to version 2025.4.1, due to an oversight in the validation performed in and , it is possible for an attacker to inject arbitrary CSS into the component. falls back to returning the or
euvd.enisa.europa.eu