Answer in brief
CVE-2023-3255 records a Medium severity (CVSS 6.5) vulnerability in Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service. The current sources do not mark it as known exploited. Affected software not mapped in the current feed; confirm the named product and version against your inventory.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
Affected software not mapped in the current feed; confirm the named product and version against your inventory.
Published upstream
Sep 13, 2023
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 1, 2026
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.
Quoted source text, attributed separately from HOL analysis.