What’s Vulnerable › Vulnerabilities

CVE-2026-87824: zstd-jni 1.3.3-1 through 1.5.7-13 Out-of-Bounds Read via Zstd.trainFromBufferDirect

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-09 · updated 2026-09-20
• Weakness: CWE-125

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.

Affected products

• luben zstd-jni: from 1.3.3-1 before 1.5.7-14 — fixed in 1.5.7-14

How to fix

Upgrade to a fixed version: luben zstd-jni 1.5.7-14. Check the vendor advisory for mitigations.

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

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