CVE-2026-105959 (GCVE-0-2026-105959)

Vulnerability from cvelistv5 – Published: 2026-10-16 11:53 – Updated: 2026-10-20 20:43
VLAI
Title
Spice-server: spice: heap buffer overflow via glz dictionary max_encoders integer truncation
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 14:04 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1070 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
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Date Public
2026-10-08 11:00
Credits
Upstream acknowledges Tristan Madani (Talence Security) as the original reporter.
Show details on NVD website
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