CVE-2026-89045 zstd-jni 1.4.8-4 through 1.5.7-13 Denial of Service via Negative Length
Attackers can cause a denial of service in zstd-jni by passing negative length values, triggering infinite loops that block thread access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89045?
CVE-2026-89045 is a medium-severity denial of service vulnerability in luben zstd-jni, published on 10 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
zstd-jni versions 1.4.8-4 through 1.5.7-13 fail to validate negative length parameters in ZstdInputStreamNoFinalizer.read(), allowing attackers to trigger infinite loops. Attackers can pass negative length values to cause the read method to spin indefinitely while holding the stream monitor, blocking all other threads from accessing the stream.
Weakness: CWE-835
Which versions are affected by CVE-2026-89045?
How do I fix CVE-2026-89045?
Upgrade to a fixed version.
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-2026-89045 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-89045 exists.
Sources
Also known as CLEANSTART-2026-CN35932, CLEANSTART-2026-FK53142, CLEANSTART-2026-OP88753, CLEANSTART-2026-PD97726, CLEANSTART-2026-WP99791, DEBIAN-CVE-2026-89045 and 3 more.