CVE-2021-38408: A stack-based buffer overflow vulnerability in Advantech WebAccess Versions 9.02 and prior caused by a lack of proper validation of the length of user-supplied…

PriorityP269critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

11.57%

95.5th percentile

A stack-based buffer overflow vulnerability in Advantech WebAccess Versions 9.02 and prior caused by a lack of proper validation of the length of user-supplied data may allow remote code execution.

Affected

1 ranges

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

Detection & IOCsextracted from sources · hover to see the quote

→Target affected product: Advantech WebAccess versions 9.02 and prior. Identify and monitor these assets on the network as exploitation requires no privileges or user interaction. ↗
→The vulnerability is a stack-based buffer overflow triggered by user-supplied data without length validation; monitor for anomalously large input payloads sent to WebAccess service endpoints. ↗

·No known public exploits specifically targeting this vulnerability were available at time of advisory publication; detection posture should be updated as public PoCs emerge. ↗
·No patched version was available at time of advisory; Advantech was still working on a fix, so version-based detection of patched vs. unpatched instances may not be reliable until an updated release is confirmed. ↗

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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