CVE-2021-3520

There's a flaw in lz4. An attacker who submits a crafted file to an application linked with lz4 may be able to trigger an integer overflow, leading to calling of memmove() on a negative size argument, causing an out-of-bounds write and/or a crash. The greatest impact of this flaw is to availability, with some potential impact to confidentiality and integrity as well.

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

3.4% chance of exploitation in the next 30 days; higher than 88% of CVEs (scores of 2026-10-25)

CWEs

CWE-190, CWE-787

Published

2021-06-02

Modified

2026-10-14

Record from

the NVD, synced 2026-10-19

Affected

• lz4_project:lz4
• netapp:active_iq_unified_manager
• netapp:cloud_backup
• netapp:ontap_select_deploy_administration_utility
• oracle:communications_cloud_native_core_policy
• oracle:zfs_storage_appliance_kit
• splunk:universal_forwarder

References

• https://bugzilla.redhat.com/show_bug.cgi?id=1954559
• https://security.netapp.com/advisory/ntap-20211104-0005/
• https://www.oracle.com//security-alerts/cpujul2021.html
• https://www.oracle.com/security-alerts/cpuapr2022.html
• https://www.oracle.com/security-alerts/cpuoct2021.html

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