7.5High
CVE-2026-87824
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.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 32% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 7.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- CVSS v4
- 8.7
- Weakness
- CWE-125
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-09
- Last modified
- 2026-09-09
- Sources
- NVD
References
- https://github.com/luben/zstd-jni
- https://github.com/luben/zstd-jni/blob/v1.5.7-13/src/main/java/com/github/luben/zstd/Zstd.java
- https://github.com/luben/zstd-jni/blob/v1.5.7-13/src/main/native/jni_zdict.c
- https://github.com/luben/zstd-jni/commit/53d3c6342883f7d6717b2477a7f9c1b4a4a56980
- https://github.com/luben/zstd-jni/commit/bba6cfca2c0897f1fa004f4193247479f10da853
- https://github.com/luben/zstd-jni/releases/tag/v1.5.7-14
- https://github.com/luben/zstd-jni/security/advisories/GHSA-257p-3h6w-pg7h
- https://www.vulncheck.com/advisories/zstd-jni-1.3.3-1-through-1.5.7-13-out-of-bounds-read-via-zstd-trainfrombufferdirect