Salesforce infrastructure abuse
Identifies messages that resemble credential theft, originating from Salesforce. Salesforce infrastrcture abuse has been observed recently to send phishing attacks.
Sublime rule (View on GitHub)
1name: "Salesforce infrastructure abuse"
2description: "Identifies messages that resemble credential theft, originating from Salesforce. Salesforce infrastrcture abuse has been observed recently to send phishing attacks."
3type: "rule"
4severity: "medium"
5source: |
6 type.inbound
7
8 // we look at the return-path because many times in the abuse
9 // we've seen, the From is a custom domain
10 and headers.return_path.domain.root_domain == "salesforce.com"
11 and length(attachments) == 0
12 // there are external links (not org or SF domains)
13 and length(filter(body.links,
14 .href_url.domain.domain not in $org_domains
15 and .href_url.domain.root_domain not in (
16 "salesforce.com",
17 "force.com",
18 "site.com", // salesforce CRM
19 "agentforce.com"
20 )
21 )
22 ) > 0
23 and (
24 (
25 any(ml.nlu_classifier(body.current_thread.text).intents,
26 .name == "cred_theft" and .confidence == "high"
27 )
28 and ml.nlu_classifier(body.current_thread.text).language == "english"
29 )
30 // subject match when cred_theft doesn't match
31 // high confidence observed subject intros in the format of "Urgent Thing: ..."
32 or regex.icontains(subject.subject,
33 '^(?:(?:Final|Last)?\s*Warning|(?:Final|Last|Legal|Critical|Content Violation)?\s*(?:Alert|Noti(?:ce|fication))|Appeal Required|Time.Sensitive|Critical.Alert|Important|Copyright Issue)\s*:\s*'
34 )
35 or any(ml.logo_detect(file.message_screenshot()).brands,
36 .name in ("Facebook", "Meta", "Instagram", "Threads")
37 and .confidence in ("medium", "high")
38 )
39 // any of the links are for newly registered domains
40 or any(filter(body.links,
41 .href_url.domain.domain not in $org_domains
42 and .href_url.domain.root_domain not in (
43 "salesforce.com",
44 "force.com",
45 "site.com", // salesforce CRM
46 "agentforce.com"
47 )
48 ),
49 network.whois(.href_url.domain).days_old < 30
50 )
51 // all links lead to a url shortener domain
52 or (
53 length(body.links) > 0
54 and all(body.links, .href_url.domain.root_domain in $url_shorteners)
55 )
56 )
57 and 1 of (
58 ( // sender domain matches no body domains
59 length(body.links) > 0
60 and all(body.links,
61 (
62 .href_url.domain.root_domain != sender.email.domain.root_domain
63 and .href_url.domain.root_domain not in (
64 "salesforce.com",
65 "force.com",
66 "site.com",
67 "agentforce.com"
68 )
69 )
70 or .href_url.domain.root_domain is null
71 )
72 ),
73 any(recipients.to,
74 .email.domain.valid
75 and any(body.links,
76 strings.icontains(.href_url.url, ..email.email)
77 or any(beta.scan_base64(.href_url.url,
78 format="url",
79 ignore_padding=true
80 ),
81 strings.icontains(., ...email.email)
82 )
83 or any(beta.scan_base64(.href_url.fragment, ignore_padding=true),
84 strings.icontains(., ...email.email)
85 )
86 // cloudflare turnstile or phishing warning page
87 or strings.icontains(ml.link_analysis(., mode="aggressive").final_dom.display_text,
88 "cloudflare"
89 )
90 )
91 ),
92 regex.icontains(subject.subject,
93 "termination.*notice",
94 "38417",
95 ":completed",
96 "[il1]{2}mit.*ma[il1]{2} ?bo?x",
97 "[il][il][il]egai[ -]",
98 "[li][li][li]ega[li] attempt",
99 "[ng]-?[io]n .*block",
100 "[ng]-?[io]n .*cancel",
101 "[ng]-?[io]n .*deactiv",
102 "[ng]-?[io]n .*disabl",
103 "action.*required",
104 "abandon.*package",
105 "about.your.account",
106 "acc(ou)?n?t (is )?on ho[li]d",
107 "acc(ou)?n?t.*terminat",
108 "acc(oun)?t.*[il1]{2}mitation",
109 "access.*limitation",
110 "account (will be )?block",
111 "account.*de-?activat",
112 "account.*locked",
113 "account.*restrict",
114 "account.*re-verification",
115 "account.*security",
116 "account.*suspension",
117 "account.has.been",
118 "account.has.expired",
119 "account.will.be.blocked",
120 "account v[il]o[li]at",
121 "activity.*acc(oun)?t",
122 "almost.full",
123 "app[li]e.[il]d",
124 "appeal required",
125 "authenticate.*account",
126 "been.*suspend",
127 "clos.*of.*account.*processed",
128 "confirm.your.account",
129 "copyright (?:restriction|infringment)",
130 "courier.*able",
131 "crediential.*notif",
132 "Critical Alert",
133 "deactivation.*in.*progress",
134 "delivery.*attempt.*failed",
135 "document.received",
136 "documented.*shared.*with.*you",
137 "dropbox.*document",
138 "e-?ma[il1]+ .{010}suspen",
139 "e-?ma[il1]{1} user",
140 "e-?ma[il1]{2} acc",
141 "e-?ma[il1]{2}.*up.?grade",
142 "e.?ma[il1]{2}.*server",
143 "e.?ma[il1]{2}.*suspend",
144 "email.update",
145 "faxed you",
146 "final notice",
147 "fraud(ulent)?.*charge",
148 "from.helpdesk",
149 "fu[il1]{2}.*ma[il1]+[ -]?box",
150 "has.been.*suspended",
151 "has.been.limited",
152 "have.locked",
153 "he[li]p ?desk upgrade",
154 "heipdesk",
155 "i[il]iega[il]",
156 "ii[il]ega[il]",
157 "immediate action",
158 "incoming e?mail",
159 "incoming.*fax",
160 "lock.*security",
161 "ma[il1]{1}[ -]?box.*quo",
162 "ma[il1]{2}[ -]?box.*fu[il1]",
163 "ma[il1]{2}box.*[il1]{2}mit",
164 "ma[il1]{2}box stor",
165 "mail on.?hold",
166 "mail.*box.*migration",
167 "mail.*de-?activat",
168 "mail.update.required",
169 "mails.*pending",
170 "messages.*pending",
171 "missed.*shipping.*notification",
172 "missed.shipment.notification",
173 "must.update.your.account",
174 "new [sl][io]g?[nig][ -]?in from",
175 "new voice ?-?mail",
176 "notifications.*pending",
177 "office.*3.*6.*5.*suspend",
178 "office365",
179 "on google docs with you",
180 "online doc",
181 "password.*compromised",
182 "periodic maintenance",
183 "potential(ly)? unauthorized",
184 "refund not approved",
185 "restrictions applied",
186 "report",
187 "revised.*policy",
188 "scam",
189 "scanned.?invoice",
190 "secured?.update",
191 "security breach",
192 "securlty",
193 "signed.*delivery",
194 "social media",
195 "status of your .{314}? ?delivery",
196 "susp[il1]+c[il1]+ous.*act[il1]+v[il1]+ty",
197 "suspicious.*sign.*[io]n",
198 "suspicious.activit",
199 "temporar(il)?y deactivate",
200 "temporar[il1]{2}y disab[li]ed",
201 "temporarily.*lock",
202 "time.sensitive",
203 "un-?usua[li].activity",
204 "unable.*deliver",
205 "unauthorized.*activit",
206 "unauthorized.device",
207 "unauthorized.use",
208 "undelivered message",
209 "unread.*doc",
210 "unusual.activity",
211 "upgrade.*account",
212 "upgrade.notice",
213 "urgent message",
214 "urgent.verification",
215 "v[il1]o[li1]at[il1]on security",
216 "va[il1]{1}date.*ma[il1]{2}[ -]?box",
217 "verification ?-?require",
218 "verification( )?-?need",
219 "verify.your?.account",
220 "web ?-?ma[il1]{2}",
221 "web[ -]?ma[il1]{2}",
222 "will.be.suspended",
223 "your (customer )?account .as",
224 "your.office.365",
225 "your.online.access",
226 "Critical.Notice",
227 "Restore.Access",
228 // https://github.com/sublime-security/static-files/blob/main/suspicious_subjects.txt
229 "account has been limited",
230 "action required",
231 "almost full",
232 "apd notifi cation",
233 "are you at your desk",
234 "are you available",
235 "attached file to docusign",
236 "banking is temporarily unavailable",
237 "bankofamerica",
238 "closing statement invoice",
239 "completed: docusign",
240 "de-activation of",
241 "delivery attempt",
242 "delivery stopped for shipment",
243 "detected suspicious",
244 "detected suspicious actvity",
245 "docu sign",
246 "document for you",
247 "document has been sent to you via docusign",
248 "document is ready for signature",
249 "docusign",
250 "encrypted message",
251 "failed delivery",
252 "fedex tracking",
253 "file was shared",
254 "freefax",
255 "fwd: due invoice paid",
256 "has shared",
257 "inbox is full",
258 "invitation to comment",
259 "invitation to edit",
260 "invoice due",
261 "left you a message",
262 "message from",
263 "new message",
264 "new voicemail",
265 "on desk",
266 "out of space",
267 "password reset",
268 "payment status",
269 "quick reply",
270 "re: w-2",
271 "required",
272 "required: completed docusign",
273 "remittance",
274 "ringcentral",
275 "scanned image",
276 "secured files",
277 "secured pdf",
278 "security alert",
279 "new sign-in",
280 "new sign in",
281 "sign-in attempt",
282 "sign in attempt",
283 "staff review",
284 "suspicious activity",
285 "unrecognized login attempt",
286 "upgrade immediately",
287 "urgent",
288 "wants to share",
289 "w2",
290 "you have notifications pending",
291 "your account",
292 'your (?:\w+\s+){0,1}\s*account',
293 "your amazon order",
294 "your document settlement",
295 "your order with amazon",
296 "your password has been compromised",
297 ),
298 any($suspicious_subjects, strings.icontains(subject.subject, .))
299 )
300 and (
301 // if the From is a custom domain, check that it's an unknown sender
302 // otherwise, it should be from salesforce
303 (
304 sender.email.domain.domain == "salesforce.com"
305 and any(headers.hops,
306 any(.fields,
307 .name == "X-SFDC-EmailCategory"
308 and .value in (
309 "apiMassMail",
310 "networksNewUser",
311 "Not Specified"
312 )
313 )
314 )
315 // negate "meta" emails from the mentioned org itself
316 // for example, subject: "a sandbox has been deleted for org ID, a1b2c3"
317 // the org ID will appear in the X-SFDC-LK header
318 and not any(headers.hops,
319 any(.fields,
320 .name == "X-SFDC-LK"
321 and strings.ends_with(subject.subject, .value)
322 )
323 )
324 )
325 or (
326 (
327 (
328 profile.by_sender().prevalence in ("new", "outlier")
329 and not profile.by_sender().solicited
330 )
331 or (
332 profile.by_sender().any_messages_malicious_or_spam
333 and not profile.by_sender().any_messages_benign
334 )
335 )
336
337 // negate highly trusted sender domains unless they fail DMARC authentication
338 and (
339 (
340 sender.email.domain.root_domain in $high_trust_sender_root_domains
341 and not headers.auth_summary.dmarc.pass
342 )
343 or sender.email.domain.root_domain not in $high_trust_sender_root_domains
344 )
345 )
346 )
347attack_types:
348 - "Credential Phishing"
349tactics_and_techniques:
350 - "Evasion"
351 - "Social engineering"
352detection_methods:
353 - "Content analysis"
354 - "Header analysis"
355 - "Natural Language Understanding"
356 - "URL analysis"
357id: "78a77c70-4008-545a-812f-bde793b72c29"