CVE-2026-85584 SiYuan before v3.8.2 Denial of Service via Auth Throttle
Unauthenticated attackers can exhaust memory and degrade service availability in SiYuan by submitting repeated authentication requests with unique invalid usernames.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-85584?
CVE-2026-85584 is a high-severity denial of service vulnerability in siyuan-note siyuan, published on 4 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
SiYuan versions before v3.8.2 contain a denial of service vulnerability in the publish-service Basic Auth throttle that stores failed-attempt state using attacker-controlled usernames without enforcing capacity limits or eviction policies. Unauthenticated attackers can submit repeated authentication requests with unique invalid usernames to exhaust memory and increase synchronization overhead, degrading service availability.
Weakness: CWE-770
Which versions are affected by CVE-2026-85584?
How do I fix CVE-2026-85584?
No fix has been published for CVE-2026-85584 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-2026-85584 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-85584 exists.
Sources
Also known as GHSA-2x7j-p79w-7744, GHSA-f2hr-7qxv-2pwm.