Heap disclosure and crash via unchecked bounds
Published Sep 9, 2026 · Updated Sep 9, 2026
Out-of-bounds read in Luben zstd-jni 1.2.0 through 1.5.7-13 allows remote attackers to disclose heap data or crash the JVM. ZstdDictCompress checks only whether offset exceeds the array length, then passes unchecked offset and length values to a native dictionary copy. Exploitation requires a consuming application to pass attacker-controlled constructor arguments; no write or code-execution primitive is reported.
Summary
What happened
Out-of-bounds read in Luben zstd-jni 1.2.0 through 1.5.7-13 allows remote attackers to disclose heap data or crash the JVM. ZstdDictCompress checks only whether offset exceeds the array length, then passes unchecked offset and length values to a native dictionary copy. Exploitation requires a consuming application to pass attacker-controlled constructor arguments; no write or code-execution primitive is reported.
The record
- CVE
- CVE-2026-87795
- Published
- Sep 9, 2026
- Updated
- Sep 9, 2026
- Vendor
- Luben
- Product
- zstd-jni
- Classifications
- CWE-125, CWE-20, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 9, 2026CVE publishedPublication date reported by the CVE source.
- Sep 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.2.0 <1.5.7-14
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- ZstdDictCompress oversized-length crash proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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