Digital Employee ExperienceApplication · Teamviewer

CVE-2026-23563

HIGH · 7.1 CVSS v3.1 Published 2026-01-29
Fix available
A fix is available. Upgrade to 26.1 or later.
See remediation →
73/100
Remediation priority · Elevated
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Improper Link Resolution Before File Access (invoked by 1E‑Explorer‑TachyonCore‑DeleteFileByPath instruction) in TeamViewer DEX - 1E Client before version 26.1 on Windows allows a low‑privileged local attacker to delete protected system files via a crafted RPC control junction or symlink that is followed when the delete instruction executes.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The 1E Client (TeamViewer DEX) before version 26.1 on Windows contains an improper link resolution vulnerability in the DeleteFileByPath instruction. The instruction follows crafted RPC control junctions or symlinks without proper validation, allowing a low-privileged local attacker to delete protected system files by pointing the delete operation to sensitive locations via a symlink or junction.

MitigationUpgrade the 1E Client to version 26.1 or later. Additionally, restrict file deletion permissions for low-privileged users and monitor for suspicious junction/symlink creation combined with the affected service activity.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Digital Employee ExperienceApplication
Affected:< 26.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify 1E Client installation
    Check for the 1E Client service or executable. On Windows, open Services and look for '1E Client' or check Program Files for the 1E folder. Alternatively, run 'sc query' or check registry under HKLM\SOFTWARE\1E
    Affected if The 1E Client service or executable is present on the system
  2. Determine installed version
    Right-click the 1E Client executable (typically in C:\Program Files\1E\Client\ or C:\Program Files (x86)\1E\Client\), select Properties, and check the File Version. Or run '1EClient.exe /version' if supported
    Affected if The version shown is below 26.1 (e.g., 26.0, 25.x, or earlier)
  3. Confirm DeleteFileByPath feature accessibility
    Identify if the 1E Client exposes its instruction set or API to low-privileged users. Check the service configuration and permissions using 'sc qc 1EClient' and review ACLs on the 1E Client program directory
    Affected if The DeleteFileByPath instruction is accessible to non-admin users or the service runs with elevated privileges but accepts input from low-privileged contexts
  4. Audit for suspicious symlinks or junctions
    Use ' junction' or 'dir /AL /S' commands to enumerate junction points and symbolic links on the system, particularly in user-writable directories like Temp, AppData, or where the 1E Client processes files
    Affected if Junctions or symlinks exist that point to protected system directories (e.g., Windows\System32) and were created recently or coincide with 1E Client activity

A system is affected if the 1E Client (TeamViewer DEX) version is below 26.1 and the DeleteFileByPath instruction is accessible to or exploitable by low-privileged users.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 26.1 or later
Fixed in 26.1
Interim mitigation

Upgrade the 1E Client to version 26.1 or later. Additionally, restrict file deletion permissions for low-privileged users and monitor for suspicious junction/symlink creation combined with the affected service activity.

Recommended fix High confidence

1E Client version 26.1

  1. Verify current 1E Client version by checking Add/Remove Programs or running '1E Client --version' in command prompt
  2. Download the latest 1E Client version 26.1 or later from the official 1E/TeamViewer support portal
  3. Create a backup of current 1E Client configuration files located in the installation directory
  4. Stop the 1E Client service before upgrading (run 'net stop TachyonCore' or use Services.msc)
  5. Run the 1E Client installer with elevated (Administrator) privileges
  6. Follow the on-screen installation wizard to complete the upgrade
  7. Restart the 1E Client service after installation (run 'net start TachyonCore' or use Services.msc)
  8. Verify the upgrade was successful by checking the installed version matches 26.1 or later
Caveat Review 1E Client 26.1 release notes for any configuration or behavioral changes from prior versions before deploying in production

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Digital Employee Experience Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-23563 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data