Medium severity · published Oct 12, 2026
CVE-2026-109246
FreeRDP before 3.32.0 Shadow Server Divide-by-Zero via Frame Acknowledge PDU
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
FreeRDP before 3.32.0 contains a divide-by-zero vulnerability in the freerdp-shadow-cli shadow server: the frame id in a client's Frame Acknowledge PDU is stored without a range check, so the in-flight frame count in shadow_encoder_inflight_frames() can underflow. An authenticated client can acknowledge a frame id one greater than the last frame sent, causing shadow_encoder_create_frame_id() to divide by zero (SIGFPE) and terminate the process, disconnecting all viewers.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
before 3.32.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-109246
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-109246
vendor-advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-6vjv-4hm3-6698
third-party-advisory
https://www.vulncheck.com/advisories/freerdp-before-3.32.0-shadow-server-divide-by-zero-via-frame-acknowledge-pdu
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