CVE-2023-3255
CWE-835Published: September 13, 2023· Updated: Jun 17, 2026
Official Description
A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service.
Technical Analysis
CVE-2023-3255 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (9)
Quick Facts
Related CVEs (CWE-835)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2023-3255 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts