8.2High
CVE-2026-87823
zstd-jni before 1.5.7-14 performs 32-bit signed bounds checks on three direct-ByteBuffer frame-size native methods, allowing out-of-bounds memory reads via negative or overflowing offsets. Attackers can supply negative offset values near Integer.MIN_VALUE to read unmapped memory, causing JVM termination or extracting arbitrary frame size data from unintended memory locations.
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 36% 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
- 8.2 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H- CVSS v4
- 8.8
- Weakness
- CWE-190
- 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_zstd.c
- https://github.com/luben/zstd-jni/commit/46dcb2a54c8b8f2ce2cad7187a7513f509c533ac
- https://github.com/luben/zstd-jni/commit/d7a1c99322d5e1fc71932e722c0b5bb2fc525d3f
- https://github.com/luben/zstd-jni/releases/tag/v1.5.7-14
- https://github.com/luben/zstd-jni/security/advisories/GHSA-jfr6-9xqw-2g2q
- https://www.vulncheck.com/advisories/zstd-jni-1.1.1-through-1.5.7-13-out-of-bounds-read-via-direct-bytebuffer-frame-size-methods
- https://github.com/luben/zstd-jni/security/advisories/GHSA-jfr6-9xqw-2g2q