CVE-2021-38389: Advantech WebAccess versions 9.02 and prior are vulnerable to a stack-based buffer overflow, which may allow an attacker to remotely execute code.

PriorityP263critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

10.37%

95.2th percentile

Advantech WebAccess versions 9.02 and prior are vulnerable to a stack-based buffer overflow, which may allow an attacker to remotely execute code.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
advantech	webaccess	<= 9.0.2	—
advantech	webaccess	All – 9.02	—

Detection & IOCsextracted from sources · hover to see the quote

→CVE-2021-38389 is a stack-based buffer overflow (CWE-121) in Advantech WebAccess versions 9.02 and prior, exploitable remotely with no authentication and low attack complexity (CVSS v3 9.8, AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), potentially leading to remote code execution. ↗
→No known public exploits specifically targeting CVE-2021-38389 were identified at time of advisory publication; monitor for novel exploit attempts against WebAccess 9.02 and prior. ↗

·Affected versions are WebAccess 9.02 and prior; Advantech released version 9.1.1 to address the stack-based buffer overflow (CVE-2021-38389). Ensure patched version is confirmed before clearing detection coverage. ↗
·The vulnerability is network-accessible with no authentication required; WebAccess instances exposed to the internet or business networks without firewall isolation are at highest risk. ↗

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P

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