Zoom Workplace: Buffer overflow in Zoom Phone feature allows privilege escalation
Summary
A buffer overflow (CWE-120) in the Zoom Phone feature of Zoom Workplace clients may allow an attacker with network access to escalate privileges. The Zoom bulletin describes an unauthenticated attacker, but the CVSS vector requires low privileges and user interaction, so the real precondition is unclear. Exposure is mainly on endpoints where Zoom Phone is in use.
Affected
- Zoom Workplace on all supported platforms (Windows, macOS, Android, iOS) before 7.2.0
- Relevant only where the Zoom Phone feature is used
- Zoom VDI and Meeting SDK-based apps: not verified
Fixed in
- Zoom Workplace 7.2.0 or later
- Fix for the 7.1 branch: unconfirmed. One press source mentions 7.1.9, but Zoom has not confirmed it in its bulletin.
Workaround
Unknown. No workaround is documented. Zoom recommends updating to the latest version.
Exploitation
- No evidence of exploitation in the wild.
- Not listed in CISA KEV.
- EPSS 0.00252 (Rapid7 data).
- No public proof of concept known.
- Reported by Kasif Dekel of Neo Security.
Our recommendation
- Inventory Zoom Workplace versions on all endpoints, including VDI.
- Update to Zoom Workplace 7.2.0 or later, prioritising endpoints where Zoom Phone is enabled.
- Check Zoom bulletin ZSB-26020 and the NVD entry for the confirmed precondition and any branch-specific fixes.
- Monitor for vendor updates and exploitation reports.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Zoom Security Bulletin ZSB-26020 www.zoom.com
- Zoom Security Bulletin index www.zoom.com
- CVE record summary (threatint) cve.threatint.com
- Vulners CVE-2026-53420 vulners.com
- Vulners CVELIST record (CNA platforms) vulners.com
- Cyberpress: Zoom patches four high-severity vulnerabilities cyberpress.org
- SecurityOnline: Zoom Workplace vulnerabilities October 2026 securityonline.info
- Strix CVE-2026-53420 www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 21:26.
Original description (NVD)
Buffer overflow in a Zoom Phone feature of Zoom Workplace Clients may allow an unauthenticated user to conduct a escalation of privilege via network access.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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