This is a summary of the AI-generated 10-question deep analysis. The full version (longer answers, follow-up Q&A, related CVEs) requires login. Read the full analysis β
Q1What is this vulnerability? (Essence + Consequences)
π¨ **Essence**: Misskey < 2025.2.1 fails to validate the relationship between `id` and `url` fields in ActivityPub objects.β¦
π‘οΈ **Root Cause**: **CWE-346** (Origin Validation Error). The system does not sufficiently verify that the `id` and `url` fields of an ActivityPub object match or are legitimately linked.β¦
π₯ **Affected**: **misskey-dev/misskey**. Specifically, all versions **prior to 2025.2.1**. If you are running an older build, you are vulnerable. π **Published**: 2025-03-10.
Q4What can hackers do? (Privileges/Data)
π **Attacker Capabilities**: Can **forge ActivityPub objects**. This compromises data integrity. While Confidentiality (C:L) is low, the ability to inject fake posts or identities is **High**.β¦
π **Exploitation Threshold**: **LOW**. CVSS Vector: `AV:N/AC:L/PR:N/UI:N`. No Authentication (PR:N), No User Interaction (UI:N), Low Complexity (AC:L). It is easily exploitable over the network without credentials.
Q6Is there a public Exp? (PoC/Wild Exploitation)
π¦ **Public Exploit**: **No**. The `pocs` field is empty. No Proof of Concept or wild exploitation code is currently available in the provided data. However, the low CVSS complexity suggests it is easy to write one.
Q7How to self-check? (Features/Scanning)
π **Self-Check**: Scan for **Misskey** instances running version **< 2025.2.1**. Check the `id` vs `url` consistency in ActivityPub payloads if you have access to logs.β¦
β **Official Fix**: **YES**. Patched in version **2025.2.1**. π **Reference**: [GitHub Advisory GHSA-6w2c-vf6f-xf26](https://github.com/misskey-dev/misskey/security/advisories/GHSA-6w2c-vf6f-xf26). Upgrade immediately!
Q9What if no patch? (Workaround)
π§ **No Patch Workaround**: If you cannot upgrade, **disable external ActivityPub interactions** or strictly filter incoming objects. Validate `id` and `url` manually at the proxy level.β¦
π₯ **Urgency**: **HIGH**. Priority: **CRITICAL**. Due to `PR:N` (No Auth) and `I:H` (High Integrity), this is a severe threat to federated trust. Patch to **2025.2.1** or later ASAP. πββοΈπ¨