# CVE-2026-106450: yawkat LZ4 Java: LZ4FrameInputStream reallocates block buffers for every frame, allowing CPU and GC amplification from small inputs > Attackers can cause CPU and memory exhaustion in applications using the LZ4 Java library by sending crafted compressed streams with many empty frames. - **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 6 Oct 2026 - **Updated:** 9 Oct 2026 - **Also known as:** CLEANSTART-2026-CE18531, CLEANSTART-2026-GP35995, CLEANSTART-2026-KZ34714, CLEANSTART-2026-LM18724, CLEANSTART-2026-QB31666, CLEANSTART-2026-TP92049, CLEANSTART-2026-XJ09918, DEBIAN-CVE-2026-106450, ECHO-42aa-021e-f029, GHSA-gm45-99xc-r7wv, MINI-24rp-mh85-mg82, MINI-27r9-v59m-5rvj, MINI-3672-p84j-rffq, MINI-3p35-54rg-63q4, MINI-4ww7-r5vw-r2c9, MINI-652f-3r7f-c993, MINI-6pjh-693f-62ch, MINI-7ccm-q89p-f8ph, MINI-7wcp-jpcc-cmhx, MINI-8m8j-wvhv-3982, MINI-8v95-mh8m-rmmq, MINI-8x25-cxqv-385v, MINI-963f-9cm5-g2p2, MINI-9h5g-93m9-q77h, MINI-9px6-g6mh-rq97, MINI-9qrv-j7c7-m6jx, MINI-chmq-c2rr-jcfr, MINI-fpgx-293q-f762, MINI-fv8r-m3xv-q34g, MINI-gxwg-3cw3-24mg, MINI-hfqh-hp55-5gx2, MINI-jmxv-v64h-2fvh, MINI-jrw8-57q9-4j3x, MINI-m43p-x24w-jcxc, MINI-m8x7-4p98-fm65, MINI-m94p-vp53-26vf, MINI-mpww-2f4j-685g, MINI-rp9m-6q88-6pf5, MINI-vcwf-fjc7-wpw3, MINI-vrj5-3875-q78m, MINI-vx4x-42r4-4x88, MINI-w6f9-x5f6-c4vf, MINI-w6hj-vxpv-h49v, MINI-wpj5-cj9j-vrmr, MINI-x57q-w5vj-p8q4, MINI-xq72-x22x-j7f7, MINI-xrrq-348w-5w68, MINI-xx2x-c4w7-h8m5, UBUNTU-CVE-2026-106450 ## What is CVE-2026-106450? CVE-2026-106450 is a medium-severity denial of service vulnerability in yawkat lz4-java, published on 6 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description yawkat LZ4 Java provides LZ4 compression for Java. Prior to 1.11.4, net.jpountz.lz4.LZ4FrameInputStream readHeader() allocates two new 4 MiB block buffers whenever a maximum-block-size frame header is read, and the default concatenated-frame mode allows attacker-controlled streams containing many minimal empty frames to trigger roughly 8 MiB of allocation for every 11 input bytes. The stream produces no decompressed output while consuming CPU and garbage-collection time, so decompressed-size limits do not mitigate the issue; readSingleFrame mode is not affected. This issue is fixed in version 1.11.4. Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling) ## Which versions are affected by CVE-2026-106450? 4 open source packages ship an affected version, including at.yawk.lz4:lz4-java and org.lz4:lz4-java. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `at.yawk.lz4:lz4-java` | Maven | All versions | 1.11.4 | | `at.yawk.lz4:lz4-java` | Maven | All versions | 1.11.4 | | `org.lz4:lz4-java` | Maven | All versions to 1.8.1 | None | | `org.lz4:lz4-java` | Maven | All versions to 1.8.1 | None | ## How do I fix CVE-2026-106450? Upgrade at.yawk.lz4:lz4-java to 1.11.4 or later. ## Is CVE-2026-106450 being exploited? There is no known exploitation of CVE-2026-106450 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-106450 and fix it if it is affected. What it is: CVE-2026-106450 is a medium-severity denial of service vulnerability in yawkat lz4-java, published on 6 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-106450 in the wild and no public exploit code. Affected packages and fixed versions: - at.yawk.lz4:lz4-java (Maven): affected all versions; fixed in 1.11.4 - at.yawk.lz4:lz4-java (Maven): affected all versions; fixed in 1.11.4 - org.lz4:lz4-java (Maven): affected all versions up to 1.8.1; no fix listed - org.lz4:lz4-java (Maven): affected all versions up to 1.8.1; no fix listed Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-106450/ (Markdown: https://insights.sbomify.com/CVE-2026-106450/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-106450 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-106450 - OSV: https://osv.dev/vulnerability/CVE-2026-106450 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-106450/ Summaries are generated and may contain mistakes; the official description above is the record.