- Before
- Starts with the clocks: which patches are near day 35, which installs missed their outage. “Thirty-five days sounds like a lot until a vendor hides the notice in a portal PDF.”
- Now
- Opens a dial where the red sector is the work, finds the evaluation and any plan already drafted with the notice sentence behind each decision, and signs.
How OT patch management works: one RTU notice, from day 31 to a signed plan
Lumina Utilities runs 312 Cyber Assets at 9 sites — five substations, the Saltmere power station, two control centres and the Wrenfield water works. On Tue 22 Sep, Halvard Controls posted security notice HCSA-2026-14 on its customer portal. Lumina last evaluated that source on Sat 12 Sep. Here is Tue 13 Oct, screen by screen, in the working solution.
- 01Morning
The queue is a 35-day dial, not a spreadsheet
Noor Haddad · OT security engineerNoor owns the patch evaluations for the substations and the power station. Her home is a dial of 35 days with a bead for each of the 47 open patches: the inner ring counts the days to evaluate, the outer ring the days to install or plan. Days 25–30 are amber, 31–35 red, and the severity bands past day 35 are printed under the dial. Below it, a tile for each of the 23 sources shows where its cycle stands.
“47 patches open on 312 Cyber Assets at 9 sites · 19 to evaluate · 28 to install or plan · 12 plans running · 0 late this year”
- 0206:00 sweep
HCSA-2026-14 reaches day 31 and turns red
Clock keeperThe Source watcher found the notice the day it was posted and the Inventory matcher matched 14 HC-560 RTUs. On Wed 7 Oct, day 25, the Clock keeper reminded Noor and Elena Marsh; there was still no evaluation. At this morning's sweep the hand moves from day 30 to 31, and the bead for HC-560 firmware 4.2.9 — an authentication bypass in the RTU's web configuration interface, CVSS 8.8 — turns red. Four days are left to evaluate, by Sat 17 Oct.
“06:00 · HCSA-2026-14 reached day 31 with no evaluation — escalated to Noor Haddad and Elena Marsh”
- 03One click
Evaluate now: the agents draft the whole evaluation
Source watcher · Inventory matcher · Applicability assessorNoor clicks Evaluate now. The Source watcher reads the 4-page notice signed by Halvard PSIRT. The Inventory matcher lists 14 HC-560 RTUs at 6 sites. The Applicability assessor finds 11 affected and 3 not applicable, at 0.96 confidence. The Outage fitter places 7 installs before Tue 17 Nov — Pennick on 27 Oct, Brackwater on 3 Nov, Ashgrove on 4 Nov — and flags that Corvane's next window is 7 days too late.
“Outage fitter · Corvane misses the deadline — next window: T2 maintenance Tue 24 Nov, 7 days late”
- 04The notice
Every decision rests on a sentence of the supplier's notice
Applicability assessorThe patch file shows Halvard's notice with the sentences that decide applicability marked and numbered, and margin notes beside them. Firmware 4.2.7 and 4.2.8 fall inside the affected range; Holloway's two RTUs and Saltmere's one run 4.3.0, installed 9 Jun. The note on remediation adds Lumina's own operating rule: losing RTU telemetry at a 400 kV or 132 kV substation needs a planned outage.
Affected: “HC-560 Remote Terminal Unit, all hardware revisions, firmware 4.0.0 through 4.2.8.” Not affected: “The issue is resolved in firmware 4.3.0 and later.”
- 05Per asset
Fourteen RTUs, fourteen decisions, each with its reason
Noor Haddad · OT security engineerThe decision table lists every RTU by tag, bay and firmware: applicable or not applicable, the reason with its citation, the action and the date. COR-RTU-401 to 404 go into mitigation plan MP-2026-031 with the install on 24 Nov. The Pennick RTUs are installed in the bay outage on Tue 27 Oct, Brackwater in feeder maintenance on Tue 3 Nov, Ashgrove in planned maintenance on Wed 4 Nov. Noor can change any decision before she signs.
“14 HC-560 RTUs · 11 applicable · 3 not applicable · drafted · you sign”
- 06The outage plan
Every install placed in the next outage that beats its deadline
Outage fitterOutage fit lays the next 60 days of planned outages at all nine sites against each patch's deadline. 13 of 15 install groups fit: 141 assets across 8 sites are booked into outages before their deadlines. Two miss. The four Corvane RTUs need Bays 1, 2, 5 and 6 out, and that is the T2 transformer maintenance on Tue 24 Nov. At Saltmere, VPA-2026-19 misses too, because the Unit 2 outage moved from 2 Nov to 16 Nov.
“Install or plan by Tue 17 Nov; the next window covering Bays 1, 2, 5 and 6 is T2 maintenance on Tue 24 Nov.”
- 0706:03
The plan template opens already filled in
Mitigation plan drafterMP-2026-031 is drafted from template MT-RTU-02, with controls taken from the supplier's own workarounds. Disable the RTU web configuration interface from the Corvane engineering workstation — no outage needed, reversible — by Thu 15 Oct (Callum Reid). Block TCP 443 to the four RTUs at the substation firewall (Noor Haddad). Alert on any connection attempt (Security operations). Install 4.2.9 in the T2 maintenance, by Thu 26 Nov.
“Complete by Sat 28 Nov 2026 · 46 days · inside the 60-day limit, so no delegate approval needed”
- 0809:41 · day 0
Signed on day 0 of the action clock
Noor Haddad · OT security engineerNoor signs the evaluation and the plan together. The red bead leaves the inner ring and starts again on the outer ring at day 0, with 35 days left to install or plan, due Tue 17 Nov. The Clock keeper logs the evaluation date and starts the action clock. Every affected RTU is now booked into an outage or covered by a dated plan.
“Signed on day 0 of the action clock · all 35 days to spare · plan MP-2026-031 complete by Sat 28 Nov”
- 0910:05
The plan on record, with its evidence list and approvals
Elena Marsh · CIP compliance analystThe full plan shows the security patch, why it cannot be installed in time, the four assets, the timeframe, the four actions with owners and dates, and the evidence to collect: a configuration export showing the HTTPS server off, the firewall rule export, the monitoring rule ID and an install record with the firmware version for each RTU. Elena reviews it at 10:05. Victor Anand, the CIP Senior Manager's delegate, is needed only for a revision or an extension.
“The Clock keeper asks for each on its date.”
- 10The same morning
Six GPS clocks with no patch source — found before the audit
Inventory matcherThe sweep also compares the inventory's 41 models with the source list. Six Bexley Time BT-90 GPS clocks at Pennick, added on Mon 21 Sep by the time-sync upgrade WO-26-40118, run updateable firmware 1.4.2 but have no tracked source. Noor adds Bexley Time as a source; its clock starts, with the first evaluation due by Tue 17 Nov.
“They are updateable (firmware 1.4.2), so CIP-007-6 R2.1 needs a source. Without one, no evaluation clock ever starts.”