CVE-2026-28432 HTTP signature verification can be bypassed
Attackers can bypass HTTP signature verification in Misskey, potentially impersonating federated entities or bypassing security checks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-28432?
CVE-2026-28432 is a high-severity vulnerability in misskey-dev misskey, published on 9 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Misskey is an open source, federated social media platform. All Misskey servers prior to 2026.3.1 contain a vulnerability that allows bypassing HTTP signature verification. Although this is a vulnerability related to federation, it affects all servers regardless of whether federation is enabled or disabled. This vulnerability is fixed in 2026.3.1.
Weakness: CWE-347
Which versions are affected by CVE-2026-28432?
It affects 1 product.
Products include Misskey Misskey.
How do I fix CVE-2026-28432?
No fix has been published for CVE-2026-28432 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-28432 being exploited?
There is no known exploitation of CVE-2026-28432 in the wild and no public exploit code.
Other vulnerabilities in misskey-dev misskey
- CVE-2025-25306 Misskey's Incomplete Patch of CVE-2024-52591 Leads to Forgery of Federated Notes
- CVE-2023-49079 Misskey's missing signature validation allows arbitrary users to impersonate any remote user.
- CVE-2026-28431 Misskey lacks proper authorization checks and input validation
- CVE-2023-52139 Misskey vulnerable to improper authorization when accessing with third-party application
- CVE-2024-52590 Missing validation allows spoofed profiles in Misskey
Sources
Also known as GHSA-grwc-c762-gcvp.