CVE-2021-34410

Root privilege escalation via user-writable installer bundle

Published Sep 27, 2021 · Updated Aug 4, 2024

Local privilege escalation in Zoom Plugin for Microsoft Outlook for Mac before 5.0.25611.0521 allows local users to gain root access. The installer unpacks an application bundle into a user-writable location, allowing local replacement of bundle contents before root-level use. Exploitation requires local low-privileged access and an installation event; successful abuse executes attacker-controlled code as root.

CVSS severity7.8
High
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Local privilege escalation in Zoom Plugin for Microsoft Outlook for Mac before 5.0.25611.0521 allows local users to gain root access. The installer unpacks an application bundle into a user-writable location, allowing local replacement of bundle contents before root-level use. Exploitation requires local low-privileged access and an installation event; successful abuse executes attacker-controlled code as root.

The record

CVE
CVE-2021-34410
Published
Sep 27, 2021
Updated
Aug 4, 2024
Vendor
Zoom Video Communications, Inc.
Product
Zoom Microsoft Outlook Plugin for Windows
Classifications
CWE-732, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 27, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Zoom Plugin for Microsoft Outlook for Mac before version 5.0.25611.0521

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Zoom Video Communications, Inc. · Zoom Microsoft Outlook Plugin for Windowsversion=Zoom Plugin for Microsoft Outlook for Mac before version 5.0.25611.0521

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-732Incorrect Permission Assignment for Critical Resource
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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