Trend Micro InterScan Web Security Virtual Appliance (IWSVA) DecryptPasswd Stack-based Buffer Overflow

critical Nessus Plugin ID 148336
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The remote host is running an application that is affected by a remote code execution vulnerability.


The Trend Micro InterScan Web Security Virtual Appliance (IWSVA) is affected by a remote code execution vulnerability. A stack-based buffer overflow condition exists in the DecryptPasswd function in due to improper validation of user-supplied data before copying it to a fixed-size, stack-based buffer via the strcpy function. An unauthenticated, remote attacker can exploit this, via a specially crafted HTTP message, to cause a denial of service condition or the execution of arbitrary code.

Note that the appliance is reportedly affected by other vulnerabilities; however, this plugin has not tested for those issues.


Upgrade to the IWSVA version 6.5 build 1919 or later.

See Also

Plugin Details

Severity: Critical

ID: 148336

File Name: trendmicro_iwsva_cve-2020-28578.nbin

Version: 1.6

Type: remote

Family: Firewalls

Published: 4/6/2021

Updated: 7/22/2021

Dependencies: trendmicro_iwsva_detect.nbin

Risk Information

CVSS Score Source: CVE-2020-28578


Risk Factor: Medium

Score: 5.9


Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:trendmicro:interscan_web_security_virtual_appliance

Required KB Items: installed_sw/Trend Micro IWSVA Web UI

Exploit Ease: No known exploits are available

Patch Publication Date: 11/16/2020

Vulnerability Publication Date: 11/16/2020

Reference Information

CVE: CVE-2020-28578