Vulnerability · Published Oct 16, 2026 · Assigned by redhat
CVE-2026-105959Spice-server: spice: heap buffer overflow via glz dictionary max_encoders integer truncation
High 7.5
In plain English
A high-severity integer overflow in Red Hat Enterprise Linux 6 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.5%top 58.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A flaw was found in spice-server. The GLZ encoder dictionary restore path truncates a size_t allocation size to int when calling the malloc callback, allowing a malicious authenticated SPICE client during VM live migration to trigger a massive heap buffer overflow by sending a crafted max_encoders value in migration data.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | spice | no fix listed | DEBIAN-CVE-2026-105959 |
| Debian:13 | spice | no fix listed | DEBIAN-CVE-2026-105959 |
| Debian:14 | spice | no fix listed | DEBIAN-CVE-2026-105959 |
| Ubuntu:22.04:LTS | spice | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:24.04:LTS | spice | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:26.04:LTS | spice | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:26.10 | spice | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:22.04:LTS | spice-gtk | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:24.04:LTS | spice-gtk | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:26.04:LTS | spice-gtk | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:26.10 | spice-gtk | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:22.04:LTS | spice-protocol | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:24.04:LTS | spice-protocol | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:26.04:LTS | spice-protocol | no fix listed | UBUNTU-CVE-2026-105959 |
| Ubuntu:26.10 | spice-protocol | no fix listed | UBUNTU-CVE-2026-105959 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 6 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
Weakness: CWE-190 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- https://access.redhat.com/security/cve/CVE-2026-105959 vdb-entry, x_refsource_REDHAT
- RHBZ#2554008 issue-tracking, x_refsource_REDHAT
- https://gitlab.freedesktop.org/spice/spice/-/merge_requests/253