7.5 CVE-2026-49494

Enriched by CISA
 

Comodo Internet Security's firewall driver Inspect.sys contains an integer underflow in its IPv6 packet parser. The parser decrements an unsigned 64-bit payload-length value (taken from the IPv6 fixed header's payload length field) by the size of each IPv6 extension header without validating it, so a packet whose declared payload length is smaller than the sum of its extension-header lengths underflows the value to a near-maximal 64-bit integer. Because IPv6 parsing occurs before firewall rule enforcement, a remote, unauthenticated attacker can send a single crafted IPv6 packet - even to a host with all ports blocked - to trigger an out-of-bounds read (and, on a separate code path, an oversized memcpy) in the Windows kernel at DISPATCH_LEVEL, crashing the system (BSOD).
https://nvd.nist.gov/vuln/detail/CVE-2026-49494

Categories

CWE-191 : Integer Underflow (Wrap or Wraparound)
This can happen in signed and unsigned cases.

References


 

AFFECTED (from MITRE)


Vendor Product Versions
Comodo Comodo Internet Security
  • ≤ 12.3.4.8162 [affected]
© 2022 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation.

CPE

cpe start end
Configuration 1
cpe:2.3:a:comodo:internet_security:*:*:*:*:*:*:*:* <= 12.3.4.8162


REMEDIATION




EXPLOITS


Exploit-db.com

id description date
No known exploits

POC Github

Url
No known exploits

Other Nist (github, ...)

Url
No known exploits


CAPEC


Common Attack Pattern Enumerations and Classifications

id description severity
No entry