CVE-2019-3973

Comodo Antivirus versions 11.0.0.6582 and below are vulnerable to Denial of Service affecting CmdGuard.sys via its filter port "cmdServicePort". A low privileged process can crash CmdVirth.exe to decrease the port's connection count followed by process hollowing a CmdVirth.exe instance with malicious code to obtain a handle to "cmdServicePort". Once this occurs, a specially crafted message can be sent to "cmdServicePort" using "FilterSendMessage" API. This can trigger an out-of-bounds write if lpOutBuffer parameter in FilterSendMessage API is near the end of specified buffer bounds. The crash occurs when the driver performs a memset operation which uses a size beyond the size of buffer specified, causing kernel crash.

CVSS v3.0

5.5 MEDIUMCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS v2.0

4.9 MEDIUMAV:L/AC:L/Au:N/C:N/I:N/A:C

EPSS

0.39% chance of exploitation in the next 30 days, 32th percentile

Published

2019-07-17

Updated

2024-08-04

Proof-of-concept exploits (1)

• https://www.tenable.com/security/research/tra-2019-34

References

• CVE Record
• NVD entry

Related

• CVE-2019-3972
• CVE-2019-3978
• CVE-2019-3971
• CVE-2019-3980
• CVE-2019-3970
• CVE-2019-3981