↳ Source GitHubRègle analytiqueMedium
Discord CDN Risky File Download (ASIM Web Session Schema)
Description
'Identifies callouts to Discord CDN addresses for risky file extensions. This detection will trigger when a callout for a risky file is made to a discord server that has only been seen once in your environment.
Unique discord servers are identified using the server ID that is included in the request URL (DiscordServerId in query). Discord CDN has been used in multiple campaigns to download additional payloads.
This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
- Type de règle
- Scheduled
- Version
- 1.1.4
- Fréquence
- 1d
- Période analysée
- 1d
- Déclenchement
- gt 0
Couverture MITRE déclarée
Sources déclarées
Métadonnées du fichier source. Aucune dépendance déduite du KQL.
Connecteurs
Types de données
Requête KQL
Requête originale, sans modification.
let discord=dynamic(["cdn.discordapp.com", "media.discordapp.com"]);
_Im_WebSession(url_has_any=discord, eventresult='Success')
| where Url has "attachments"
| extend DiscordServerId = extract(@"\/attachments\/([0-9]+)\/", 1, Url)
| summarize dcount(Url), make_set(SrcUsername), make_set(SrcIpAddr), make_set(Url), min(TimeGenerated), max(TimeGenerated), make_set(EventResult) by DiscordServerId
| mv-expand set_SrcUsername to typeof(string), set_Url to typeof(string), set_EventResult to typeof(string), set_SrcIpAddr to typeof(string)
| summarize by DiscordServerId, dcount_Url, set_SrcUsername, min_TimeGenerated, max_TimeGenerated, set_EventResult, set_SrcIpAddr, set_Url
| project StartTime=min_TimeGenerated, EndTime=max_TimeGenerated, Result=set_EventResult, SourceUser=set_SrcUsername, SourceIP=set_SrcIpAddr, RequestURL=set_Url
| where RequestURL has_any (".bin",".exe",".dll",".bin",".msi")
| extend AccountName = tostring(split(SourceUser, "@")[0]), AccountUPNSuffix = tostring(split(SourceUser, "@")[1])
Entités déclarées
Contenus associés
Liens établis à partir des identifiants déclarés et des manifests des solutions.
Traçabilité de la source
GitHubLes valeurs affichées proviennent des fichiers du dépôt Azure/Azure-Sentinel. Elles décrivent le modèle publié, pas la configuration de votre workspace.
- Commit
9800e51↗- Identifiant source
01e8ffff-dc0c-43fe-aa22-d459c4204553
Autres fichiers source 1
Detections/ASimWebSession/DiscordCDNRiskyFileDownload_ASim.yamlsource ↗GSTEP / SUIVI DU CATALOGUE
Ajouté au catalogue : 16 sept. 2026 · 05:49 UTC
Dernier changement observé : 16 sept. 2026 · 05:49 UTC