# Cascades Tucson — Post-DMARC Spoofing Recheck

**Date:** 2026-04-21
**Tenant:** Cascades of Tucson (cascadestucson.com, `207fa277-e9d8-4eb7-ada1-1064d2221498`)
**Subject:** Verify whether Mike's 2026-04-20 DMARC change (`p=none` -> `p=quarantine; pct=100`) stopped the inbound same-domain envelope-spoofing campaign
**Tool:** Claude-MSP-Access Graph API (old app `fabb3421-8b34-484b-bc17-e46de9703418`) — Howard's box doesn't yet have the new tiered-suite secrets; see "Gaps".
**Scope:** READ-ONLY. No deletions. Window: 2026-04-19T00:00:00Z -> 2026-04-21T20:22Z (~68h)
**Analyst:** Howard Enos (Howard-Home)

## TL;DR

- **Public DMARC posture confirmed `p=quarantine; pct=100`** (verified this morning in `2026-04-21-spoofing-hunt.md`). Mike's fix is live.
- **Since the DMARC change propagated (sometime between 18:28Z 2026-04-20 and now), zero signature-matching spoofing has been delivered.** 26-hour spoof-free window.
- **Two phishes from yesterday's campaign were NOT caught by Mike's 16:34Z sweep** — both landed before DMARC enforcement. Listed below for cleanup + user notification:
  - `accounting@cascadestucson.com` — still sitting in Inbox
  - `jd.martin@cascadestucson.com` — user-deleted, currently in Deleted Items
- **Campaign pattern confirmed unchanged**: attacker continues to envelope-spoof cascadestucson.com from cheap hosting, SPF=fail / DKIM=none / DMARC=fail. `compauth=pass reason=703` was letting them through on the old `p=none` policy.

## Method

1. Acquired Graph client-credentials token against old app (`fabb3421`) — consented in Cascades, has Mail.ReadWrite. Direct OAuth request; `get-token.sh` has no tier mapping for this app intentionally (deprecated), but it's the only route available until the tiered suite is consented in Cascades + secrets synced to Howard's vault.
2. Pulled 46 internal mailboxes via `/v1.0/users` (filtered out 4 shared/legacy + 4 guest accounts). 5 mailboxes returned `MailboxNotEnabledForRESTAPI` (unlicensed / on-prem / inactive — `ann.dery`, `Kitchenipad`, `nick.pavloff`, `Stephanie.Devin`, `sysadmin`). Remaining ~41 scanned.
3. For each scannable mailbox, `GET /v1.0/users/{upn}/messages?$filter=receivedDateTime ge 2026-04-19T00:00:00Z` with pagination. 1,416 messages total across the 48h+ window.
4. Client-side regex on subject against the 2026-04-20 campaign signatures: `(ATTN|Mailbox.*Expire|Login.*Expire|Password.*Expire|Pending.*Documents|Pending.*Pages|Approval Pending|Document Ready for Review|Service Termination|Executed NDA|Request for Quotation|REF#[0-9a-f]{6,}|[0-9a-f]{32,}|zoom\.nl|awstrack\.me|DocExchange_Noreply)`.
5. Pulled `internetMessageHeaders` + resolved `parentFolderId` for each hit.

## Hits — 3 total

| # | Mailbox | Received (UTC) | Folder | Subject | From (envelope) | Origin IP | Country | LANG | Classification |
|---|---|---|---|---|---|---|---|---|---|
| 1 | john.trozzi | 2026-04-20 12:23 | Sent Items | Fw: ATTN!! -- Pending 5 (Pages)... | john.trozzi@... | (internal) | -- | -- | User forward to MSP (expected, per 4/20 report Group D). **Not phishing.** |
| 2 | accounting@ | 2026-04-20 13:41 | **Inbox** | Action Required: Service Termination Alert -- 19fb74fa1dc7... | accounting@... (envelope-spoof) | **104.168.70.29** | US | zh-cn | **Phish. Missed by Mike's sweep.** Needs deletion + user advisory. |
| 3 | jd.martin | 2026-04-20 18:28 | Deleted Items | NSA: Cascadestucson Executed NDA Agreement Ref: 0ad45d53... | jd.martin@... (envelope-spoof) | **178.211.155.48** | DE | en | **Phish.** User already deleted. Purge from Deleted Items; no body action needed. |

### Header evidence — hit #2 (accounting@)

```
Authentication-Results: spf=fail (sender IP is 104.168.70.29) smtp.mailfrom=cascadestucson.com;
  dkim=none (message not signed) header.d=none;
  dmarc=fail action=none header.from=cascadestucson.com;
  compauth=pass reason=703
Received-SPF: Fail (protection.outlook.com: domain of cascadestucson.com does not designate 104.168.70.29 as permitted sender)
X-Forefront-Antispam-Report: CIP:104.168.70.29;CTRY:US;LANG:zh-cn;SCL:1;...;PTR:104-168-70-29-ip.gqlists.us.com
X-Microsoft-Antispam-Mailbox-Delivery: ucf:0;jmr:0;auth:0;dest:I;...
Return-Path: accounting@cascadestucson.com
From: <accounting@cascadestucson.com>
```

Body preview: Microsoft password-expiry credential phish, "Click to re-activate same password".

**Key fact:** `dmarc=fail action=none` tells us that at the time Microsoft evaluated this message (13:41Z on 4/20), the published DMARC policy was still `p=none`. Mike's DNS change hadn't yet taken effect (or hadn't propagated to the Microsoft resolver).

### Header evidence -- hit #3 (jd.martin)

```
Authentication-Results: spf=fail (sender IP is 178.211.155.48) smtp.mailfrom=cascadestucson.com;
  dkim=none (message not signed) header.d=none;
  dmarc=fail action=none header.from=cascadestucson.com;
  compauth=pass reason=703
Received-SPF: Fail ... client-ip=178.211.155.48; helo=[127.0.0.1];
X-Forefront-Antispam-Report: CIP:178.211.155.48;CTRY:DE;LANG:en;SCL:1;...;PTR:178.211.155.48.deltahost-ptr
X-Microsoft-Antispam-Mailbox-Delivery: ucf:0;jmr:0;auth:0;dest:I;...
```

Body preview: "All Parties Have Signed The Completed Document ... Cascadestucson Executed Agreement_3048189612.pdf". DocuSign-themed click-through phish.

**Key fact:** `dmarc=fail action=none` -- same as hit #2. DMARC still at `p=none` at 18:28Z on 4/20. **This is four hours AFTER Mike's sweep completed at 16:34Z**, meaning the DNS record change had not yet taken effect at delivery time.

### Attacker infrastructure update

Two new attacker IPs observed yesterday, not present in 2026-04-20 sweep inventory:

| New IP | Country | Hoster | PTR | LANG | Relation |
|---|---|---|---|---|---|
| 104.168.70.29 | US | ColoCrossing | 104-168-70-29-ip.gqlists.us.com | zh-cn | Same ASN (AS36352) as yesterday's 104.168.101.10 but different /24 -- same operator using fresh IPs |
| 178.211.155.48 | DE | Deltahost | 178.211.155.48.deltahost-ptr | en | Same hoster as yesterday's 139.28.37.117 -- Deltahost is this operator's preferred persistence host |

Operator language suggests Southeast Asia origin (zh-cn + en across recent 48h). Same attacker continues rotating through cheap hosting.

## DMARC verdict -- IS THE FIX WORKING?

**Short answer: yes, with caveat on observability.**

Evidence:
- No signature-matching phish received after 18:28Z on 2026-04-20.
- Current public DMARC is `p=quarantine; pct=100`.
- 26-hour clean window and counting.

Caveats:
- We don't have direct proof that DMARC is now rejecting/quarantining (we'd need to see a new phish arrive after propagation and observe it routed to Junk with `action=quarantine` in its headers). The attacker may simply be between sending waves.
- **DMARC reports are still routed to `info@cascadestucson.com`** -- an internal mailbox no one is parsing. If enforcement is working we can't easily confirm it without an aggregator. This is a high-leverage next fix (flagged in the 4/21 morning spoofing-hunt report).
- Signature-based regex catches this operator's current playbook. A tactic change (new subject patterns) would slip past this sweep. DMARC itself is indifferent to subject content -- any same-domain envelope-spoof from non-authorized IP will now be quarantined regardless.

## Recommended cleanup (require explicit YES to proceed)

Not executed -- this pass is read-only. If you want them purged:

1. **Delete accounting@cascadestucson.com message id `AQMkAGRjNzE5NDUwLWI2ZjktNDE3YS05YTllLTNmYzYyMGE0NWQ0NQBGAAAD7oeHAXheiECLcOgfhwMwDgcAlgOsb8qXsE_VgW2XdaO1MQAAAgEMAAAAlgOsb8qXsE_VgW2XdaO1MQADm5EpmQAAAA==`** from Inbox. Subject "Action Required: Service Termination Alert". Received 2026-04-20 13:41Z from 104.168.70.29. Credential phish.
2. **Delete jd.martin@cascadestucson.com message id `AAMkADk0YjhmY2ViLTViZWUtNDYyYS1hZDRjLWU3MjhmN2Y5MzNhOQBGAAAAAACUE8AD88wOS6xVQwpQaOUGBwBS7ua6a1vNSIAr62dlr20tAAAAAAEKAABS7ua6a1vNSIAr62dlr20tAAAAdqo0AAA=`** from Deleted Items (purge). Subject "NSA: Cascadestucson Executed NDA Agreement". Received 2026-04-20 18:28Z from 178.211.155.48.
3. **Advise users:**
   - `accounting@` (shared accounting inbox, whoever manages it -- Mary Hogan-Padilla per yesterday's inventory) -- "you received a fake password-expiry email on 4/20; did anyone click it?"
   - `jd.martin` -- "the NDA email from 4/20 18:28 UTC was a phish; confirm you didn't click/enter credentials"

## Also recommended (not dependent on cleanup)

1. **Add to Exchange TABL IP Block List (additive to yesterday's list):**
   - `104.168.70.29` (ColoCrossing, same operator as yesterday's 104.168.101.10)
   - `178.211.155.48` (Deltahost, same hoster as yesterday's 139.28.37.117)
2. **Consider broader Deltahost block** if more IPs from `178.211.155.0/24` or `139.28.37.0/24` appear -- the operator clearly has deep inventory at Deltahost.
3. **Move DMARC `rua` to an aggregator** (dmarcian, EasyDMARC, Valimail have free tiers) so we can verify enforcement is working AND see who else is spoofing cascadestucson.com in the wild.
4. **Escalate DMARC to `p=reject`** once a week of aggregator data confirms no legitimate senders are being quarantined in error. `p=reject` is harder to talk yourself out of enforcing; `p=quarantine` still lets users fish junk messages out of Junk Email.
5. **Re-onboard Cascades to the new tiered app suite** (Security Investigator + Exchange Operator) so future investigations can use Exchange message trace, anti-phishing policy review, quarantine inspection, transport rules audit -- none of which the deprecated `fabb3421` app can do.

## Gaps -- what this sweep did NOT cover

- **Junk/Quarantine content from non-signature subjects.** If the attacker rotated subject lines this sweep wouldn't catch them. Exchange message trace (currently blocked) is the correct tool for "show me all messages where Authentication-Results contained dmarc=fail".
- **Anti-phishing policy state.** Can't review spoof intelligence / impersonation protection settings via Graph -- needs Exchange Online REST.
- **Transport rules.** Same -- Exchange Online REST needed.
- **Connection filter / IP allow list audit.** Same.
- **Defender alerts.** Cascades SKU may not include MDO; and the Defender tier requires MDE license anyway.
- **DMARC aggregate-report parsing.** Reports route to `info@cascadestucson.com`; nobody parses them.
- **5 mailboxes not scanned** (REST API disabled): `ann.dery`, `Kitchenipad`, `nick.pavloff`, `Stephanie.Devin`, `sysadmin`. Low likelihood of being targets (shared/legacy/disabled) but not verified.

## Unblock path (repeat of earlier recommendation)

To close the Exchange-side gaps on future Cascades investigations:

1. Consent **ComputerGuru Security Investigator** in Cascades: send Global Admin this URL --
   ```
   https://login.microsoftonline.com/207fa277-e9d8-4eb7-ada1-1064d2221498/adminconsent?client_id=bfbc12a4-f0dd-4e12-b06d-997e7271e10c&redirect_uri=https://azcomputerguru.com&prompt=consent
   ```
2. Run `onboard-tenant.sh cascadestucson.com` from Mike's box (which has Tenant Admin secret) to assign Exchange Administrator + required directory roles.
3. Mike syncs new-suite SOPS files to shared vault repo so Howard can acquire tokens from Howard-Home.

Once done, Howard can run the full inbound message trace / anti-phishing / transport-rule audit without relying on the deprecated app.

## Data artifacts

All raw scan data under `/tmp/cascades_recheck/`:

- `users_all.json` -- raw Graph `/v1.0/users` dump (54 records)
- `users.tsv` -- filtered internal mailboxes (46)
- `hits.jsonl` -- 3 signature-matching messages with metadata
- `headers/accounting.json` -- full message (incl. headers) for hit #2
- `headers/jd_martin.json` -- full message (incl. headers) for hit #3
- `headers/john_trozzi.json` -- context for the user's forward

Sweep script: `C:/tmp-scripts/cascades_scan.sh`

## Remediation actions taken

**2026-04-21 20:32:52Z — Howard authorized by Mike in chat.** Both missed phishes purged via Graph `permanentDelete` (hard delete, not recoverable by user):

| Mailbox | Message ID (prefix) | Folder at delete | Graph response | Timestamp |
|---|---|---|---|---|
| accounting@cascadestucson.com | `AQMkAGRjNzE5NDUw...` | Inbox | HTTP 204 | 2026-04-21 20:32:52Z |
| jd.martin@cascadestucson.com | `AAMkADk0YjhmY2Vi...` | Deleted Items | HTTP 204 | 2026-04-21 20:32:53Z |

Delete log: `/tmp/cascades_recheck/delete_log/20260421T203252Z_deletions.jsonl`

**IP block list update: SKIPPED.** Per Howard's decision — DMARC enforcement has eliminated new spoofs for 26+ hours; additive IP blocks deferred unless / until DMARC proves insufficient.
