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An empty railway platform at night under overhead lighting
work / DW-2601

Reached the signalling network from a ticket kiosk

A payment terminal on a station concourse turned out to share a VLAN with the operational network four hops away.

client
A national rail operator
sector
Transport / OT
service
Red teaming
duration
7 weeks
4
hops from kiosk to signalling VLAN
0
alerts raised during initial access
31
detection rules written afterwards
the situation

The operator had segmented its corporate and operational networks years earlier and had the architecture diagrams to prove it. The diagrams were accurate. The estate was not — a decade of station refurbishments had quietly reconnected things nobody was tracking.

Rolling stock stabled under overhead line equipment at dusk

Transport / OT

what we did
01

Physical entry to three stations using contractor pretexts agreed in advance with the security director.

02

Implanted a monitored device behind a concourse ticket kiosk and left it for eleven days.

03

Mapped reachable services from that position and found a maintenance jump host trusted by the operational side.

04

Stopped at the boundary of the signalling network, evidenced reachability, and did not cross it.

selected findings
as they appear in the report
reffindingseverity
DW-2601-01Flat VLAN shared between concourse payment and maintenance networkscritical
DW-2601-04Jump host trusted by operational domain with no MFAcritical
DW-2601-09Contractor badges not revoked after project completionhigh
DW-2601-17No alerting on new MAC addresses in station switch closetshigh
outcome

We proved reachability, stopped, and handed the operator a segmentation programme with the four specific links that mattered ranked ahead of the ninety that did not. All four were closed within a quarter.

They found the thing we had been assured was impossible, then spent the last two weeks teaching our team to find it themselves.
Head of Cyber Security · National rail operator
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