VulnerabilityPublished 1 Oct 2025

CVE-2025-41421: TeamViewer Full Client · Link Following

Affects TeamViewer Full ClientSource CVE Database V5

Not known to be exploited · CVSS 4.7 Medium.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

4.7Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Local
Attack Complexity: High
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

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

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
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: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
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 1 Oct 2025
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 26 Oct 2026.

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 or the CVSS exploit maturity 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

Affected software

Product	Affected	Fixed in
TeamViewer Full Client	Affected =11.0.0	Fixed in–

AI-suggested

European organizations should prioritize upgrading TeamViewer Full Client and Host installations to version 15.70 or later, where this vulnerability is resolved. Until upgrades are fully deployed, organizations should enforce strict local access controls, ensuring that only trusted users have local login capabilities on devices running vulnerable versions. Endpoint protection solutions should be enhanced to detect and block suspicious symbolic link creation or manipulation activities. Implementing application whitelisting and monitoring file system changes related to update paths can provide additional layers of defense. Regular auditing of local user accounts and privilege assignments will reduce the risk of unauthorized local access. Network segmentation can limit the spread of an attacker who gains local access. Finally, organizations should maintain up-to-date incident response plans to quickly identify and remediate any exploitation attempts.

Description

Improper handling of symbolic links in the TeamViewer Full Client and Host for Windows — in versions prior to 15.70 of TeamViewer Remote and Tensor — allows an attacker with local, unprivileged access to a device lacking adequate malware protection to escalate privileges by spoofing the update file path. This may result in unauthorized access to sensitive information.

Impact

For European organizations, this vulnerability poses a risk primarily in environments where TeamViewer is used extensively for remote support and management, especially on Windows endpoints. Since exploitation requires local access and the absence of adequate malware protection, the threat is more significant in organizations with less stringent endpoint security controls or where insider threats or compromised local accounts are possible. Successful exploitation could lead to unauthorized access to sensitive corporate data, potentially including credentials, internal communications, or proprietary information. This could facilitate further lateral movement within networks or data exfiltration. The impact is heightened in sectors with strict data protection regulations such as GDPR, where unauthorized data access can lead to regulatory penalties and reputational damage. Additionally, organizations relying on TeamViewer for critical remote operations may face operational risks if attackers leverage this vulnerability to gain footholds in their systems.

CWE-59Improper Link Resolution Before File Access ('Link Following') (opens in a new tab)
Base weaknessLikelihood of exploit: MediumOWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
Architecture and Design · Separation of Privilege
Follow the principle of least privilege when assigning access rights to entities in a software system.
OWASP Cheat Sheets
Authorization (opens in a new tab)
Attack patterns
Symlink Attack (opens in a new tab)
Using Malicious Files (opens in a new tab)
Leverage Executable Code in Non-Executable Files (opens in a new tab)
Manipulating Web Input to File System Calls (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

teamviewer.com/en/resources/trust-center/security-bulletins/tv-2025-1004/ (opens in a new tab)

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 2 Oct 2025, 00:11 UTC

WeaknessesCWE-59

Technical details

References

Community reviews

Related threats