CVE-2021-3520

CRITICAL
9.8
CVSS Score
Published: June 2, 2021 at 12:32 PM UTC
Updated: October 14, 2026 at 10:17 AM UTC
7 products affected across 4 vendorsActive IQ Unified ManagerCloud BackupONTAP Select Deploy administration utility

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Severity
CRITICAL9.8
Exploit prediction
EPSS 3%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

1.8.3 ≤ v < 1.9.41.8.3
Affected range stops below 1.9.4, so it looks safe — our inference, not a vendor statement
All versions
8.2.0 ≤ v < 8.2.129.0.0 ≤ v < 9.0.69.1.0
Affected range stops below 8.2.12, so it looks safe — our inference, not a vendor statement
Affected range stops below 9.0.6, so it looks safe — our inference, not a vendor statement

References (6)

x_refsource_MISCIssue TrackingPatchThird Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1954559
x_refsource_MISCPatchThird Party Advisory
https://www.oracle.com//security-alerts/cpujul2021.html
x_refsource_MISCPatchThird Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html
x_refsource_MISCPatchThird Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html
Source: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
https://cert-portal.siemens.com/productcert/html/ssa-398330.html

SSVC — Action Prioritization

SSVCNo known exploitAutomatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-190

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