# CVE-2021-3520: lz4: The lz4 packages provide support for LZ4, a very fast, lossless compression algorithm that provides compression speed...

CVE-2021-3520 is fixed in 9 products on 1 platform, first by liblz4-1 0.0~r131-2ubuntu3.1, released April 29, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-3520
- Priority: High
- CVSS: 9.8 (Moderate)
- EPSS: 0.0340
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 29, 2021

## Description

The lz4 packages provide support for LZ4, a very fast, lossless compression algorithm that provides compression speeds of 400 MB/s per core and scales with multicore CPUs. It also features an extremely fast decoder that reaches speeds of multiple GB/s per core and typically reaches RAM speed limits on multicore systems.  Security Fix(es):  * lz4: memory corruption due to an integer overflow bug caused by memmove argument (CVE-2021-3520)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | liblz4-1 Ubuntu 18.04.6 LTS (bionic) | 0.0~r131-2ubuntu3.1 | [liblz4-1 0.0~r131-2ubuntu3.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-liblz4-1-0.0-r131-2ubuntu3.1.md) | Apr 29, 2021 |
| Linux | liblz4-1 Ubuntu 20.04 LTS (focal) | 1.9.2-2ubuntu0.20.04.1 | [liblz4-1 1.9.2-2ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-liblz4-1-1.9.2-2ubuntu0.20.04.1.md) | Apr 29, 2021 |
| Linux | liblz4-tool Ubuntu 18.04.6 LTS (bionic) | 0.0~r131-2ubuntu3.1 | [liblz4-tool 0.0~r131-2ubuntu3.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-liblz4-tool-0.0-r131-2ubuntu3.1.md) | Apr 29, 2021 |
| Linux | liblz4-tool Ubuntu 20.04 LTS (focal) | 1.9.2-2ubuntu0.20.04.1 | [liblz4-tool 1.9.2-2ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-liblz4-tool-1.9.2-2ubuntu0.20.04.1.md) | Apr 29, 2021 |
| Linux | lz4 RHEL 8 | 0:1.8.3-3.el8_4 | [RHSA-2021:2575](https://patchblox.com/security/data/fix/linux/rhsa-2021-2575.md) | Jun 29, 2021 |
| Linux | lz4 Ubuntu 20.04 LTS (focal) | 1.9.2-2ubuntu0.20.04.1 | [lz4 1.9.2-2ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-lz4-1.9.2-2ubuntu0.20.04.1.md) | Apr 29, 2021 |
| Linux | lz4 amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |
| Linux | lz4 ol 8 | 0:1.8.3-3.el8_4 | [ELSA-2021-2575](https://patchblox.com/security/data/fix/linux/elsa-2021-2575.md) | Jun 30, 2021 |
| Linux | lz4-debuginfo amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |
| Linux | lz4-debugsource amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |
| Linux | lz4-devel RHEL 8 | 0:1.8.3-3.el8_4 | [RHSA-2021:2575](https://patchblox.com/security/data/fix/linux/rhsa-2021-2575.md) | Jun 29, 2021 |
| Linux | lz4-devel amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |
| Linux | lz4-devel ol 8 | 0:1.8.3-3.el8_4 | [ELSA-2021-2575](https://patchblox.com/security/data/fix/linux/elsa-2021-2575.md) | Jun 30, 2021 |
| Linux | lz4-libs RHEL 8 | 0:1.8.3-3.el8_4 | [RHSA-2021:2575](https://patchblox.com/security/data/fix/linux/rhsa-2021-2575.md) | Jun 29, 2021 |
| Linux | lz4-libs amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |
| Linux | lz4-libs ol 8 | 0:1.8.3-3.el8_4 | [ELSA-2021-2575](https://patchblox.com/security/data/fix/linux/elsa-2021-2575.md) | Jun 30, 2021 |
| Linux | lz4-libs-debuginfo amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |
| Linux | lz4-static amzn 2023 | 1.9.4-1.amzn2023.0.2 | [ALAS2023-2023-015](https://patchblox.com/security/data/fix/linux/alas2023-2023-015.md) | Feb 17, 2023 |

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