# CVE-2026-53413 — Zoom Clients

> As of 2026-08-12, CVE-2026-53413 is a HIGH-severity vulnerability in Zoom Clients, CVSS v3.1 8.3, EPSS 0.4% (33.8th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-53413, most recently “"Zoomsday" Flaws (CVE-2026-53413, CVE-2026-53414, CVE-2026-53415) Let One Zoom Meeting Participant Attack Another”.

**Last updated:** 2026-08-12

## What is CVE-2026-53413?

Missing bounds check in the annotator function of Zoom Clients allows buffer over-write, which may allow a meeting participant to achieve remote code execution of another participant via network access.

The record classifies CVE-2026-53413 under weakness class [CWE-787](https://intel.threadlinqs.com/cwe/CWE-787). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 55 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.3 — HIGH (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H`)
- **EPSS (FIRST):** 0.4% probability of exploitation in the next 30 days, higher than 33.8% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.5/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-11, last modified 2026-08-12

## Is CVE-2026-53413 being exploited?

No public exploitation evidence for CVE-2026-53413 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-08-12. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.

## Affected products and versions

- [Zoom Communications](https://intel.threadlinqs.com/vendors/zoom-communications): Zoom Clients

## How to fix CVE-2026-53413

No vendor patch reference has been recorded for CVE-2026-53413 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-53413

1 tracked threat in the Threadlinqs corpus references CVE-2026-53413, either in the campaign’s CVE list or as an indicator on the campaign record.

- ["Zoomsday" Flaws (CVE-2026-53413, CVE-2026-53414, CVE-2026-53415) Let One Zoom Meeting Participant Attack Another](https://intel.threadlinqs.com/threat/TL-2026-2001) — CRITICAL · 2026-08-12

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-08-13. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [zoom.com](https://www.zoom.com/en/trust/security-bulletin/zsb-26015)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-53413
Full detection coverage and IOCs for threats exploiting CVE-2026-53413 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp