CVE Catalog

CVE-2026-49494

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.54%

42th percentile - higher than 42% of all known CVEs

Summary

Xcitium Client Security before 13.8.2.10019 and Comodo Internet Security through 12.3.4.8162 have an integer underflow in the firewall driver Inspect.sys. Sending a crafted IPv6 packet with payload length smaller than extension-header lengths causes an out-of-bounds read and system crash (BSOD).

Risk Assessment

A remote attacker can crash Windows systems (blue screen of death) even on hosts with all ports blocked, causing service disruption.

Recommendation

Update Xcitium Client Security to version 13.8.2.10019 or later. For Comodo Internet Security, wait for a patch from the vendor (expected by Q3 2026). Temporarily consider disabling the Inspect.sys driver if feasible.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS