---
id: "CVE-2026-105958"
kind: "vulnerability"
aliases: ["CVE-2026-105958"]
title: "spice-server: client-supplied offsets let a malicious client corrupt heap memory"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "spice-server", "fixed": [], "affected": "all versions (no fixed version published)", "ecosystem": "vendor"}]
ecosystems: []
tags: ["infrastructure", "kvm", "libvirt", "live-migration", "qemu", "rhel", "spice", "spice-server", "virtualization"]
not_affected_if: ["no-live-migration", "no-spice", "vnc-only"]
published_at: "2026-10-16T13:16:53+00:00"
first_seen_at: "2026-10-23T21:57:12+00:00"
updated_at: "2026-10-25T03:47:59+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-105958", "first_seen_at": "2026-10-23T21:57:12+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-25T03:47:59+00:00"}]
---

# spice-server: client-supplied offsets let a malicious client corrupt heap memory

During VM live migration, spice-server trusts offsets sent by a SPICE client in SPICE_MSGC_MIGRATE_DATA messages without checking bounds. A malicious authenticated client can read arbitrary heap memory or corrupt the heap through out-of-bounds reads and writes.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:spice-server affected all versions (no fixed version published) fixed ?

## How to check

Check whether spice-server is installed (rpm -q spice-server or dpkg -l | grep spice) and whether VMs use SPICE graphics with live migration (virsh dumpxml <vm> | grep -i "graphics type='spice'"). Compare against distro status; no fixed version exists yet.

## Fix

No fixed release published as of 2026-10-25 (Debian unfixed; Red Hat lists RHEL 6/7/8 as affected, no errata). Upstream fix is in spice MR 257 (https://gitlab.freedesktop.org/spice/spice/-/merge_requests/257), release not confirmed. Watch your distro's spice/spice-server package.

## Timeline

- 2026-10-23T21:57:12+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-105958
- 2026-10-25T03:47:59+00:00 analyst — Red Hat advisory read: affects spice-server in RHEL 6/7/8 (no fixed version listed); Debian bookworm/trixie/sid 'unfixed' (0.15.1-1, 0.15.2-1, 0.16.0-3). Upstream MR 257 behind Anubis, unreadable, so no upstream fixed release confirmed. No exploitation or PoC found; no social search done (no CVE-named discussion likely). Mitigation from Red Hat text.

## Documents

- [advisory] Red Hat CVE-2026-105958 https://access.redhat.com/security/cve/cve-2026-105958
- [mentions] Debian tracker CVE-2026-105958 https://security-tracker.debian.org/tracker/CVE-2026-105958

## From the sources

A flaw was found in spice-server. Multiple migration data handlers use client-supplied offsets from SPICE_MSGC_MIGRATE_DATA messages without bounds validation, allowing a malicious authenticated SPICE client during VM live migration to read arbitrary heap memory or trigger heap corruption via out-of-bounds read and write operations on the message buffer.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_