CVE-2021-34413
CVE-2021-34413 is a high-severity vulnerability in Zoom Zoom Plugin For Microsoft Outlook with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-367.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 6.0
- EPSS exploit prediction: 1% (43rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-367
- Affected product: Zoom Zoom Plugin For Microsoft Outlook
- Published:
- Last modified:
Description
All versions of the Zoom Plugin for Microsoft Outlook for MacOS before 5.3.52553.0918 contain a Time-of-check Time-of-use (TOC/TOU) vulnerability during the plugin installation process. This could allow a standard user to write their own malicious application to the plugin directory, allowing the malicious application to execute in a privileged context.
Frequently asked questions
- What is CVE-2021-34413?
- All versions of the Zoom Plugin for Microsoft Outlook for MacOS before 5.3.52553.0918 contain a Time-of-check Time-of-use (TOC/TOU) vulnerability during the plugin installation process. This could allow a standard user to write their own malicious application to the plugin directory, allowing the malicious application to execute in a privileged context.
- How severe is CVE-2021-34413?
- CVE-2021-34413 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-34413 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-34413?
- CVE-2021-34413 affects Zoom Zoom Plugin For Microsoft Outlook. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-34413?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-34413 published?
- CVE-2021-34413 was published on 2021-09-27 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:zoom:zoom_plugin_for_microsoft_outlook:*:*:*:*:*:windows:*:*
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