SmartDefragDriver.sys (2.0) in IObit Smart Defrag 6 never frees an executable kernel pool that is allocated with user defined bytes and siz…

published 2019-04-11 7y ago modified 2026-06-17 4mo ago also EUVD-2019-16053

cvss: 5.5; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits: 0; none known

SmartDefragDriver.sys (2.0) in IObit Smart Defrag 6 never frees an executable kernel pool that is allocated with user defined bytes and size when IOCTL 0x9C401CC0 is called. This kernel pointer can be leaked if the kernel pool becomes a "big" pool.

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Exploit prediction

0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

downwithup.github.io https://downwithup.github.io/CVEPosts.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	5.5	CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	2.1	AV:L/AC:L/Au:N/C:P/I:N/A:N

Classification

Weakness

CWE-401 Missing Release of Memory after Effective Lifetime

References

downwithup.github.io /CVEPosts.html
exploit, vendor-advisory
iobit.com /en/iobitsmartdefrag.php
product, vendor-advisory

Sources

CVE List CVE-2019-6493
NVD CVE-2019-6493

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