CVE-2024-49363 Uncontrolled Recursion and Asymmetric Resource Consumption (Amplification) in media/file proxy in Misskey
Remote attackers can cause denial of service in Misskey via uncontrolled recursion in the media proxy, requiring an upgrade to fix.
- 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-2024-49363?
CVE-2024-49363 is a high-severity denial of service vulnerability in misskey-dev misskey, published on 18 Dec 2024. 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. In affected versions FileServerService (media proxy) in github.com/misskey-dev/misskey 2024.10.1 or earlier did not detect proxy loops, which allows remote actors to execute a self-propagating reflected/amplified distributed denial-of-service via a maliciously crafted note. FileServerService.prototype.proxyHandler did not check incoming requests are not coming from another proxy server. An attacker can execute an amplified denial-of-service by sending a nested proxy request to the server and end the request with a malicious redirect back to another nested proxy request. Leading to unbounded recursion until the original request is timed out. This issue has been addressed in version 2024.11.0-alpha.3. Users are advised to upgrade. Users unable to upgrade may configure the reverse proxy to block requests to the proxy with an empty User-Agent header or one containing Misskey/. An attacker can not effectively modify the User-Agent header without making another request to the server.
Which versions are affected by CVE-2024-49363?
How do I fix CVE-2024-49363?
No fix has been published for CVE-2024-49363 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-49363 being exploited?
There is no known exploitation of CVE-2024-49363 in the wild and no public exploit code.
Sources
Also known as GHSA-gq5q-c77c-v236.