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highMemory Corruptionpublic exploit

CVE-2026-53413

CVE-2026-53413 — Zoom Clients - Buffer Over-write

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.

Published Updated Sources: NVD, Zoom Communications (CNA), SOCRadar CTI

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Reported

not confirmed by CISA

EPSS

6%

ahead of 92% of scored CVEs

Affects

Zoom Communications

Zoom Clients

CVSS base

8.3

high

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

No

can an attacker script all four kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

Upgrade Zoom Clients to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

  • Identify exposed assets running affected vendor/product/version combinations.
  • Prioritize based on EPSS, PoC availability, and external exposure.
  • Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

VendorProductVersionsStatus
Zoom CommunicationsZoom Clientssee referencesVulnerable

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Availability

High

Confidentiality

High

Integrity

High

Scope

Changed

Attack Complexity

High

Attack Vector

Network

Privileges Req

None

User Interaction

Required

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactSource
8.3CVSS 3.1high1.66zoom.us (CNA), Zoom Communications (CNA)

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-787 · Out-of-bounds Write

  • Modify Memory
  • DoS: Crash, Exit, or Restart
  • Execute Unauthorized Code or Commands::

Mitigation: Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.

Weakness & attack patterns

  • CWE-787Out-of-bounds Write

Inferred from the weakness class — not observed against this CVE.

CAPEC-100 · Overflow BuffersCAPEC-123 · Buffer Manipulation

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

1

Social mentions

Posts naming this CVE. Attention, not evidence of exploitation — it spikes on disclosure and decays whether or not anything is exploited.

SOCRadar14 more posts on this CVEShowing 5 of 19 · Who is discussing this CVE, and how loudlyUnlock free

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

  • Prioritize edge telemetry for network-reachable Zoom Clients.
  • Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.
web/proxy/WAF logsapplication logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

  1. 2026
  2. Added · CVSS 3.1 8.3 (AV:N)

    Aug 28, 2026 · NVD

  3. Initial · CVE published

    Aug 11, 2026 · NVD

Source activity

Readings a source repeats on a schedule, counted rather than listed.

  • TweetsAug 12, 2026 – Aug 22, 2026 · SOCRadar CTI
  • SvrsAug 12, 2026 – Aug 24, 2026 · SOCRadar CTI
  • CVE appeared in the Cve Trends.Aug 13, 2026 · SOCRadar CTI
  • Github_Repos · Github repository created, HORKimhab/CVE-2026-53413Aug 13, 2026 · SOCRadar CTI
  • CVE modified by MITRE: CVSS metrics updated.Aug 11, 2026 · SOCRadar CTI

References

1 on the record

Coverage

10 stories from the feeds we poll

Elsewhere on this site

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1

What should defenders know first?

CVE-2026-53413 is Zoom Clients - Buffer Over-write, a high vulnerability affecting Zoom Clients from Zoom Communications. The current evidence does not list it in CISA KEV, and the exploit status is: Exploitation is reported, but no independent confirmation is available in the sources we have. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.3 describes technical severity, while EPSS 6% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.