CVE-2024-39826VulnerabilityPublished 15 Jul 2024Updated 2 Oct 2025

CVE-2024-39826: Zoom Workplace Apps and SDKs · Time-of-check Time-of-use (TOCTOU) Race Condition

Affects Zoom Workplace Apps and SDKsSource CVE Database V5

Not known to be exploited · CVSS 6.8 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

6.8Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 37% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Changed
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Jul 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

European organizations should prioritize the following mitigation steps: 1) Monitor Zoom's official security advisories closely and apply patches or updates as soon as they become available to address CVE-2024-39826. 2) Restrict access to Zoom Workplace Apps and SDKs to only trusted and necessary users, enforcing strong authentication mechanisms such as multi-factor authentication (MFA) to reduce the risk of compromised accounts. 3) Implement network segmentation and strict access controls to limit the ability of authenticated users to exploit the vulnerability across different parts of the network. 4) Conduct internal audits and monitoring of Zoom chat activity and network traffic for unusual patterns that may indicate exploitation attempts. 5) Educate users about the risks of social engineering and phishing that could lead to credential compromise, which is a prerequisite for exploitation. 6) Where possible, consider alternative communication tools or configurations that minimize reliance on vulnerable components until patches are available. 7) Engage with Zoom support or security teams for guidance on temporary workarounds or configuration changes that can reduce exposure.

Description

Race condition in Team Chat for some Zoom Workplace Apps and SDKs for Windows may allow an authenticated user to conduct information disclosure via network access.

Impact

For European organizations, this vulnerability poses a significant risk to the confidentiality of sensitive communications and data shared within Zoom Workplace environments. Since the flaw allows authenticated users to potentially disclose information improperly, insider threats or compromised accounts could lead to unauthorized data exposure. This is particularly concerning for sectors handling sensitive or regulated data, such as finance, healthcare, legal, and government entities. The medium severity rating and requirement for authentication limit the risk to some extent; however, given the widespread adoption of Zoom in Europe for remote work and collaboration, the potential for lateral movement or data leakage within organizations is notable. The vulnerability could undermine trust in internal communications and complicate compliance with data protection regulations like GDPR if sensitive personal or corporate data is exposed. Additionally, the changed scope of the vulnerability means that the impact could extend beyond the immediate application, potentially affecting integrated systems or services relying on the Zoom SDKs.

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition (opens in a new tab)
Base weaknessLikelihood of exploit: Medium
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
Implementation
The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
Implementation
When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
Architecture and Design
Limit the interleaving of operations on files from multiple processes.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V1.11.3 (opens in a new tab)
V11.1.6 (opens in a new tab)
V1.11.2 (opens in a new tab)
Attack patterns
Leveraging Race Conditions via Symbolic Links (opens in a new tab)
Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

zoom.com/en/trust/security-bulletin/zsb-24023 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 4 Oct 2025, 11:03 UTC

WeaknessesCWE-367

Technical details

References

Community reviews

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