CVE-2026-49494
HIGH EPSS 41.4%
Published Jun 7, 20263w ago · Modified Jun 23, 20266d ago
8.7 CVSS 4.0
Published Jun 7, 2026 3w ago
Last Modified Jun 23, 2026 6d ago
Description
Xcitium Client Security (XCS) before 13.8.2.10019 and Comodo Internet Security (CIS) through 12.3.4.8162 (fix expected by 2026 Q3) contain an integer underflow vulnerability in the firewall driver Inspect.sys that allows remote unauthenticated attackers to crash the system by sending a crafted IPv6 packet with a declared payload length smaller than the sum of its extension-header lengths. The unsigned 64-bit payload-length value underflows to a near-maximal integer, triggering an out-of-bounds read and oversized memcpy in the Windows kernel at DISPATCH_LEVEL, resulting in a blue screen of death even on hosts with all ports blocked.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
41.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-191
References 4
- github.com https://github.com/MalwareTech/ComoDoS
- malwaretech.com https://malwaretech.com/2026/06/exploiting-a-remote-kernel-vulnerability-in-comodo-internet-security.html
- updates.xcitium.com https://updates.xcitium.com/#note11312
- vulncheck.com https://www.vulncheck.com/advisories/xcitium-client-security-comodo-internet-security-remote-dos
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.