Vulnerability · Published Sep 9, 2026 · Assigned by VulnCheck
CVE-2026-87795zstd-jni 1.2.0 through 1.5.7-13 Out-of-Bounds Read via ZstdDictCompress
High 8.2
In plain English
A high-severity out-of-bounds read in zstd-jni from luben. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)8.2High
Exploit odds (30 days)0.6%top 49.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
zstd-jni versions before 1.5.7-14 fail to validate offset and length parameters in the ZstdDictCompress constructor, allowing out-of-bounds memory reads. Attackers can supply untrusted offset or length values to read native heap memory into the compression dictionary, typically causing JVM crashes.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | zstd-jni-java | no fix listed | DEBIAN-CVE-2026-87795 |
| Debian:13 | zstd-jni-java | no fix listed | DEBIAN-CVE-2026-87795 |
| Debian:14 | zstd-jni-java | 1.5.7-23+ds-1 | DEBIAN-CVE-2026-87795 |
| Ubuntu:24.04:LTS | zstd-jni-java | no fix listed | UBUNTU-CVE-2026-87795 |
| Ubuntu:26.04:LTS | zstd-jni-java | no fix listed | UBUNTU-CVE-2026-87795 |
| Ubuntu:26.10 | zstd-jni-java | no fix listed | UBUNTU-CVE-2026-87795 |
Affected products (as reported)
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
References
- GitHub Security Advisory (GHSA-ff36-7w3w-g8rm) vendor-advisory
- Fix commit patch
- Broken bounds check at v1.5.7-13 technical-description
- Native init that trusts the offset and length technical-description
- Commit that introduced the unchecked native path technical-description, patch
- zstd-jni v1.5.7-14 Release Notes release-notes
- https://github.com/luben/zstd-jni product
- VulnCheck Advisory: zstd-jni 1.2.0 through 1.5.7-13 Out-of-Bounds Read via ZstdDictCompress third-party-advisory