CVE-2018-7499

Vulnerability

Several stack-based buffer overflow vulnerabilities exist in Advantech WebAccess versions V8.2_20170817 and prior, WebAccess versions V8.3.0 and prior, WebAccess Dashboard versions V.2.0.15 and prior, WebAccess Scada Node versions prior to 8.3.1, and WebAccess/NMS 2.0.3 and prior. These flaws reside in the handling of specially crafted requests by the web application [1]. An attacker can trigger a buffer overflow by sending a malicious payload to a vulnerable endpoint without requiring any special configuration [1].

Exploitation

An attacker can exploit these vulnerabilities remotely over the network without authentication and with low skill level [1]. The attack vector is network-based, and no user interaction is necessary. The attacker sends a crafted request containing data that overflows a stack-based buffer in the target process [1].

Impact

Successful exploitation allows the attacker to execute arbitrary code in the context of the affected application [1]. The CVSS v3 base score is 9.8 (Critical), with the vector (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating full compromise of confidentiality, integrity, and availability [1]. The advisory also notes that these vulnerabilities could lead to sensitive information disclosure and file deletion in conjunction with other flaws [1].

Mitigation

Advantech has released updated versions to address these issues: WebAccess v8.3.1, WebAccess Dashboard v2.0.16, WebAccess Scada Node v8.3.1, and WebAccess/NMS 2.0.4 or later [1]. Users should upgrade to the fixed versions immediately. ICS-CERT recommends applying vendor updates and following general security best practices such as network segmentation and minimizing exposure [1].