JVM crash and adjacent-memory disclosure via unchecked decompression
Published Nov 28, 2025 · Updated Dec 29, 2025
Out-of-bounds reads in lz4-java 1.8.0 and earlier allow remote attackers to crash a JVM or read adjacent memory via compressed input. The JNI fast decompressor calls the deprecated bounds-unsafe LZ4_decompress_fast API, while Unsafe-based Java implementations omit sufficient range checks. An application must pass attacker-controlled compressed data to an affected native-fast or Unsafe implementation; ordinary safe Java implementations instead raise an exception without disclosing memory.
Summary
What happened
Out-of-bounds reads in lz4-java 1.8.0 and earlier allow remote attackers to crash a JVM or read adjacent memory via compressed input. The JNI fast decompressor calls the deprecated bounds-unsafe LZ4_decompress_fast API, while Unsafe-based Java implementations omit sufficient range checks. An application must pass attacker-controlled compressed data to an affected native-fast or Unsafe implementation; ordinary safe Java implementations instead raise an exception without disclosing memory.
The record
- CVE
- CVE-2025-12183
- Published
- Nov 28, 2025
- Updated
- Dec 29, 2025
- Vendor
- yawkat
- Product
- lz4-java
- Classifications
- CWE-125
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 28, 2025CVE publishedPublication date reported by the CVE source.
- Dec 29, 2025Record 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=1.0.0 <=1.8.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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