Vulnerability in at.yawk.lz4:lz4-java (CVE-2026-106450)
Summary
Vulnerability in at.yawk.lz4:lz4-java (CVE-2026-106450). Risk of unauthorized operations or information disclosure. Exploitable via LZ4FrameInputStream. Mitigation: upgrade to 1.11.4 or later.
Original description
The description as published by the source.
Summary
LZ4FrameInputStream allocates two new buffers of the frame's maximum block size, up to 4 MiB each, every time it reads a frame header. Because concatenated frames are read by default, an input made of many minimal empty frames forces about 8 MiB of zeroed heap allocation for every 11 input bytes.
Details
In net.jpountz.lz4.LZ4FrameInputStream.readHeader():
maxBlockSize = frameInfo.getBD().getBlockMaximumSize();
compressedBuffer = new byte[maxBlockSize]; // Reused during different compressions
rawBuffer = new byte[maxBlockSize];
buffer = ByteBuffer.wrap(rawBuffer);
This runs for every frame, and the previous frame's arrays are never reused. A valid 11-byte frame consists of the magic number, FLG 0x60, BD 0x70 (4 MiB blocks), the header checksum, and an immediate end mark. It carries no data, yet triggers the full 8 MiB allocation. new LZ4FrameInputStream(in) reads concatenated frames by default.
In local measurements on JDK 25, 10,000 such frames (110 KB of input) took about 8 seconds of CPU to read, roughly 70 seconds per MiB of input. This was similar under G1, Parallel, Serial and ZGC. A legitimate stream costs orders of magnitude less per input byte.
Impact
Applications that decode attacker-controlled LZ4 frame data with LZ4FrameInputStream can be made to spend large amounts of CPU and GC time relative to the input size. Live heap stays bounded at about 8 MiB and the stream produces no output, so decompressed-size limits…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-106450 has been found in at.yawk.lz4:lz4-java.
Attackers can target a specific entry point like LZ4FrameInputStream over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: upgrade at.yawk.lz4:lz4-java to 1.11.4 or later.
If unsure, ask your IT team or search "at.yawk.lz4:lz4-java CVE-2026-106450" on the vendor's site.
CVE-2026-106450 (at.yawk.lz4:lz4-java) — CWE-770 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: LZ4FrameInputStream
Patched: 1.11.4 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-770) exists in at.yawk.lz4:lz4-java. Attackers reach the vulnerable code path via LZ4FrameInputStream without authentication.
Check the vendor advisory for the affected versions of at.yawk.lz4:lz4-java. Attack surface: LZ4FrameInputStream.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to 1.11.4.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで at.yawk.lz4:lz4-java を使っているサービスとバージョンを洗い出す。
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2Apply patch patch
Upgrade at.yawk.lz4:lz4-java to 1.11.4ステージング環境で 1.11.4 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com
- web github.com