Medium severity · published Jan 29, 2026
CVE-2026-23567
Integer underflow in Content Distribution Service UDP handler
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
An integer underflow in the UDP command handler of the TeamViewer DEX Client (former 1E Client) - Content Distribution Service (NomadBranch.exe) prior version 26.1 for Windows allows an adjacent network attacker to trigger a heap-based buffer overflow and cause a denial-of-service (service crash) via specially crafted UDP packets.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 29% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DE
DEX · TeamViewer
before 26.1 · source: vendor
DE
Digital Employee Experience · Teamviewer
before 26.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-23567
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-23567
Vendor Advisory
https://www.teamviewer.com/en/resources/trust-center/security-bulletins/tv-2026-1001/
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