Excessive memory allocation in LZ4 Java stream reader
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Partial Red Hat: 13 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-789.
Summary
yawkat LZ4 Java before 1.11.2 and the org.lz4:lz4-java Maven package through 1.8.1 are affected. LZ4BlockInputStream checks only that the compressed length in a legacy block header is nonnegative, then allocates a buffer of that size before reading payload data (CWE-789). An unauthenticated remote attacker can send a stream with only a header to force a near-2 GiB allocation and exhaust the JVM heap.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
yawkat LZ4 Java provides LZ4 compression for Java. Prior to 1.11.2, net.jpountz.lz4.LZ4BlockInputStream refill() validates that the compressedLen field in a legacy LZ4Block header is nonnegative but allocates a compressed-input buffer of that attacker-controlled size before reading payload data, allowing a header-only stream to request a near-2 GiB allocation and exhaust the JVM heap. Canonical writers emit raw blocks when compression is not smaller than the original block, but vulnerable readers accept non-canonical oversized compressed blocks. This issue is fixed in version 1.11.2.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| yawkat | lz4-java | before 1.11.2 | 1.11.2 | Patch available | CNA |
| — | at.yawk.lz4:lz4-java (Maven) | before 1.11.2 | 1.11.2 | Patch available | GHSA-4v53-57pg-c464 |
| — | org.lz4:lz4-java (Maven) | up to 1.8.1 | — | No fix listed | GHSA-4v53-57pg-c464 |
- lz4-java Vendoryawkat Affected before 1.11.2 Fixed in 1.11.2 Patch available CNA
- at.yawk.lz4:lz4-java (Maven) Vendor— Affected before 1.11.2 Fixed in 1.11.2 Patch available GHSA-4v53-57pg-c464
- org.lz4:lz4-java (Maven) Vendor— Affected up to 1.8.1 Fixed in — No fix listed GHSA-4v53-57pg-c464
Remediation
Upgrade yawkat lz4-java and at.yawk.lz4:lz4-java to 1.11.2. The sources list no fixed version for org.lz4:lz4-java. Red Hat lists Red Hat Enterprise Linux 8 and 9, Red Hat JBoss Enterprise Application Platform 8, Red Hat OpenShift AI (RHOAI), Red Hat build of Quarkus and other products as affected with no fix available, and Red Hat Fuse 7 with no fix planned.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA lz4-java (yawkat) Fixed in 1.11.2
- Fix · GHSA-4v53-57pg-c464 at.yawk.lz4:lz4-java (Maven) Fixed in 1.11.2 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| OpenShift Developer Tools and Services | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Fuse 7 | Affected | No fix planned: Out of support scope |
| Red Hat Hardened Images | Affected | No fix yet: Fix deferred |
| Red Hat JBoss Enterprise Application Platform 8 | Affected | No fix yet: Fix deferred |
| Red Hat JBoss Enterprise Application Platform Expansion Pack | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat build of Apache Camel 4 for Quarkus 3 | Affected | No fix yet: Fix deferred |
| Red Hat build of Apache Camel for Spring Boot 4 | Affected | No fix yet: Fix deferred |
| Red Hat build of Apicurio Registry 3 | Affected | No fix yet: Fix deferred |
| Red Hat build of Debezium 3 | Affected | No fix yet: Fix deferred |
| Red Hat build of Quarkus | Affected | No fix yet |
Timeline
- 2026-10-06 Threatist record created from CVE-2026-106452
- 2026-10-07 Affected versions changed · Red Hat
- 2026-10-07 CVSS score added · Red Hat
- 2026-10-07 CISA SSVC decision points changed
- 2026-10-07 Alias added: GHSA-4v53-57pg-c464
- 2026-10-07 Fix available: Maven/at.yawk.lz4:[email protected] · GHSA-4v53-57pg-c464
- 2026-10-07 CVSS score added · GHSA-4v53-57pg-c464
- 2026-10-07 Weakness changed · GHSA-4v53-57pg-c464
- 2026-10-07 5 new references · GHSA-4v53-57pg-c464
- 2026-10-13 Affected versions changed · Red Hat
References
More yawkat vulnerabilities
- TI-2025-40977 yawkat LZ4 Java has a possible information leak in Java safe decompressor CVSS 4.0HIGH 8.2
- TI-2026-68931 LZ4 Java native library extraction allows local file replacement CVSS 4.0HIGH 7.3
- TI-2026-68933 LZ4 Java decompressor allocates memory from untrusted length header CVSS 3.1MEDIUM 5.3
- TI-2026-68930 LZ4 Java LZ4FrameInputStream allocates memory without limits CVSS 3.1MEDIUM 5.3
- TI-2026-42755 NULL pointer dereference in yawkat lz4-java CVSS 3.1MEDIUM 6.5
- TI-2026-68929 Uncontrolled recursion in yawkat LZ4 Java LZ4BlockInputStream CVSS 3.1LOW 3.7
Sources
- CVE-2026-106452 · CVE Program
- CVE-2026-106452 · NVD
- FIRST EPSS
- GHSA-4v53-57pg-c464 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-106452 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences