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Fencer Intel
medium 5.8

CVE-2015-3963 json

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_corei…

published 2015-08-04 11 y ago modified 2026-06-17 4 mo ago also EUVD-2015-3994

cvss
5.8
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
3.7%
EPSS 3.7% chance of exploitation in 30 days, percentile 89%
public exploits
0
none known

Summary

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.

Patch / fix

  • windriver vxworks 6.7.1.1, 6.8.3, 6.9.4.4

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-15-169-01B updated cvss 5.8

Wind River VXWorks TCP Predictability Vulnerability in ICS Devices (Update B)

  • Wind River Schneider Electric SAGE 1210 RTU Wind River Schneider Electric SAGE 1230 RTU Wind River Schneider Electric SAGE 1250 RTU Wind River Schneider Electric SAGE 1310 RTU Wind River Schneider Electric SAGE 1330 RTU Wind River Schneider Electric SAGE 1350 RTU
    +12 more products
    Wind River Schneider Electric SAGE 1410 RTU Wind River Schneider Electric SAGE 1430 RTU Wind River Schneider Electric SAGE 1450 RTU Wind River Schneider Electric SAGE 2200 RTU Wind River Schneider Electric SAGE 2300 RTU Wind River Schneider Electric SAGE 2400 RTU Wind River Schneider Electric SAGE 3030 Magnum RTU Wind River Schneider Electric SAGE 3030 RTU Wind River Schneider Electric SAGE LANDAC2 Upgrade Kit Wind River VxWorks >=7, <February_13_2015, >=6.9, <6.9.4.4, >=6.8, <6.8.3, >=6.7, <6.7.1.1 Wind River VxWorks 653 Platform/Platform for Safety Critical ARINC 653 3.0, 2.5, 2.4, 2.3 Wind River VxWorks Cert 6.6.3, 6.6.4, 6.6.4.1
    affected: mitigation “Wind River has released patches and new versions to address the TCP predictability vulnerability for several versions of VxWorks” knowledge.windriver.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

3.74% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 2.0 5.8 AV:N/AC:M/Au:N/C:N/I:P/A:P

Classification

Weakness
  • CWE-330 Use of Insufficiently Random Values

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.