CVE-2026-87824 zstd-jni 1.3.3-1 through 1.5.7-13 Out-of-Bounds Read via Zstd.trainFromBufferDirect
Attackers can cause JVM termination and read memory by supplying oversized sample lengths to the zstd-jni library's training function.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-87824?
CVE-2026-87824 is a high-severity memory corruption vulnerability in luben zstd-jni, published on 9 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
zstd-jni before 1.5.7-14 fails to validate the samples buffer capacity in Zstd.trainFromBufferDirect, allowing attackers to read past buffer boundaries by supplying oversized per-sample lengths. Attackers can trigger out-of-bounds memory access by providing crafted sample length arrays that cause the native implementation to walk past the buffer allocation, resulting in JVM termination.
Weakness: CWE-125
Which versions are affected by CVE-2026-87824?
How do I fix CVE-2026-87824?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-87824 being exploited?
There is no known exploitation of CVE-2026-87824 in the wild and no public exploit code.
Sources
Also known as CLEANSTART-2026-LG38764, CLEANSTART-2026-TA23513, CLEANSTART-2026-VB49028, CLEANSTART-2026-WM83029, CLEANSTART-2026-YT55390, CLEANSTART-2026-ZG93473 and 4 more.