CVE-2015-3963

Wind River VxWorks before 5.5.1, 6.5.x through 6.7.x before 6.7.1.1, 6.8.x before 6.8.3, 6.9.x before 6.9.4.4, and 7.x before 7 ipnet_coreip 1.2.2.0, as used on Schneider Electric SAGE RTU devices before J2 and other devices, does not properly generate TCP initial sequence number (ISN) values, which makes it easier for remote attackers to spoof TCP sessions by predicting an ISN value.

Published: 2015-08-03 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2015-3963 is rated Moderate Risk (54.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 3.74%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2015-3963

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 3.00% 3.74% +0.74%
2 2025-11-10 4.71% 3.00% -1.70%
3 2025-06-08 — 4.71% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2015-3963

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 4.9 [email protected]

Weakness enumeration for CVE-2015-3963

Affected software / configurations for CVE-2015-3963

Vendor Product Version Raw CPE
windriver vxworks >= 6.5, <= 6.6 cpe:2.3:o:windriver:vxworks:*:*:*:*:*:*:*:*
windriver vxworks >= 6.7, < 6.7.1.1 cpe:2.3:o:windriver:vxworks:*:*:*:*:*:*:*:*
windriver vxworks >= 6.8, < 6.8.3 cpe:2.3:o:windriver:vxworks:*:*:*:*:*:*:*:*
windriver vxworks >= 6.9, < 6.9.4.4 cpe:2.3:o:windriver:vxworks:*:*:*:*:*:*:*:*
windriver vxworks 6.6.3 cpe:2.3:o:windriver:vxworks:6.6.3:*:*:*:cert:*:*:*
windriver vxworks 6.6.4 cpe:2.3:o:windriver:vxworks:6.6.4:*:*:*:cert:*:*:*
windriver vxworks 6.6.4.1 cpe:2.3:o:windriver:vxworks:6.6.4.1:*:*:*:cert:*:*:*
windriver vxworks 7.0 cpe:2.3:o:windriver:vxworks:7.0:*:*:*:*:*:*:*

References for CVE-2015-3963

URL Tags
http://www.schneider-electric.com/ww/en/download/document/SEVD-2015-162-01 Patch Third Party Advisory
http://www.securityfocus.com/bid/75302 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1032730 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1033181 Third Party Advisory VDB Entry
https://ics-cert.us-cert.gov/advisories/ICSA-15-169-01 Third Party Advisory US Government Resource
https://ics-cert.us-cert.gov/advisories/ICSA-15-169-01A Third Party Advisory US Government Resource
https://security.netapp.com/advisory/ntap-20160324-0001/ Third Party Advisory
cvelogic Threat Intelligence