7.7High
CVE-2026-87825
zstd-jni before 1.5.7-14 contains a use-after-free vulnerability where streams and contexts hold a dictionary's shared lock only during the load call, allowing the dictionary to be closed while still referenced. Attackers can close a dictionary after associating it with a stream or context, causing subsequent read or write operations to access freed native memory, resulting in silent data corruption or JVM crashes.
What this means for your business
- An attacker can use it only with access to the machine itself, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.1% chance of attack attempts being seen in the next 30 days, ranking above 3% 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
- 7.7 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H- CVSS v4
- 7.0
- Weakness
- CWE-416
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-09
- Last modified
- 2026-09-14
- 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/BaseZstdBufferDecompressingStreamNoFinalizer.java
- https://github.com/luben/zstd-jni/blob/v1.5.7-13/src/main/java/com/github/luben/zstd/ZstdInputStreamNoFinalizer.java
- https://github.com/luben/zstd-jni/commit/0827ed02551bbd8d6f8e4bbff99d83bf50f91938
- https://github.com/luben/zstd-jni/commit/393d7311766abbc285b149302c0fe1f94b16d555
- https://github.com/luben/zstd-jni/commit/a560131d7834598afd9cea6b7c107bc88e915936
- https://github.com/luben/zstd-jni/releases/tag/v1.5.7-14
- https://github.com/luben/zstd-jni/security/advisories/GHSA-947w-pxjj-c7m9
- https://www.vulncheck.com/advisories/zstd-jni-1.3.8-4-through-1.5.7-13-use-after-free-of-compression-and-decompression-dictionaries