Malicious PDF — malware analysis report

Static analysis result for SHA-256 d37daf4a148a541c…

MALICIOUS

PDF

67.9 KB Created: 2021-05-31 13:41:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 56d077db940e4f23d2982d2f32f4d823 SHA-1: 9280082451daa9ca7a7f3578d118e2c3ffd40715 SHA-256: d37daf4a148a541c63308ec2c03f56a259e4c1e747b18ae03706fcd80ee04672
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a lure for 'free gems in brawl stars' and embeds multiple external links, including one to 'resalured.ru'. Heuristics indicate a link farm and a detected malicious PDF, with ML classification scoring very high. The presence of 'powershell_x86.pdf' in the document text suggests an attempt to exploit or download a PowerShell-related payload, aligning with client execution techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://resalured.ru/strik?utm_term=free+gems+in+brawl+stars+no+hack
    • https://wuvonedegodufez.weebly.com/uploads/1/3/4/8/134883317/zefuleborazej.pdf
    • https://rosafuzumago.weebly.com/uploads/1/3/1/8/131857847/6d3c677a.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/fe046709-e29e-49ac-826a-9d53ca487234/what_is_powershell_x86.pdf
    • https://uploads.strikinglycdn.com/files/2688e9c4-da06-4227-bc0b-8e69ac7408fe/kaguvimisuzupibakex.pdf
    • https://uploads.strikinglycdn.com/files/91ea0d38-6f68-4d0d-99f2-9e66972fad4b/gonorrhea_treatment_guidelines_2018.pdf
    • https://uploads.strikinglycdn.com/files/4a409c07-3d28-4a18-81a4-a5d60f36e09d/everlasting_god_chords_ultimate_guitar.pdf
    • https://uploads.strikinglycdn.com/files/6cb21c72-76b5-4b80-b723-de5199b9b105/sueo_de_una_noche_de_verano_silvio_significado.pdf
    • https://uploads.strikinglycdn.com/files/3fc021fe-e503-4c26-ba40-f661da5dfe6d/99447375863.pdf
    • https://uploads.strikinglycdn.com/files/c589bea9-13c1-46fd-ba3e-5b484fa74d13/used_mtd_rear_tine_tiller_for_sale.pdf
    • https://uploads.strikinglycdn.com/files/62046eb4-c9fb-4297-af23-47af2d56afe1/sumiluvowasilojarenizefa.pdf
    • https://uploads.strikinglycdn.com/files/8191bb12-bee2-41fa-9db8-8019a8671393/century_130_mig_wire_feed_welder_parts.pdf
    • https://uploads.strikinglycdn.com/files/e394413e-4bb6-4073-953e-e40a9c2f86bc/83397675674.pdf
    • https://uploads.strikinglycdn.com/files/c80da0e7-dfd4-4bd1-8d72-030a5741c6b0/78723390850.pdf
    • https://uploads.strikinglycdn.com/files/a0046a53-3073-4aaa-8dc5-5115a109e0f0/zedefi.pdf
    • https://uploads.strikinglycdn.com/files/8cced24f-5f86-4325-9057-4af00f72e7ff/biwewowawizujakuk.pdf
    • https://uploads.strikinglycdn.com/files/d1f27138-c270-4afc-ae82-c9a2e8fdd944/99276005374.pdf
    • https://uploads.strikinglycdn.com/files/1f6c13e6-56d6-4bd2-a934-0f2ae57a7a26/what_old_coins_are_valuable_uk.pdf
    • https://uploads.strikinglycdn.com/files/8fa9c171-046d-49c2-8fb3-f4dd298573ee/37559131347.pdf
    • https://uploads.strikinglycdn.com/files/bb2a05ab-a29c-4434-bb46-0ccc00d5d0ff/maytag_5000_series_dryer_f01_error_code.pdf
    • https://uploads.strikinglycdn.com/files/404da13e-4b88-4b23-893c-e401df0bfab6/46052646067.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • https://uploads.strikinglycdn.com/files/2
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cecd.bin
66b60aca5a92e21b5c016e0a3b34987ec28a0c52a9fa59f97b6395c71e522795
pdf-font-stream PDF embedded font (sfnt) at offset 0xCECD 5464 bytes
font_01_sfnt_off0000e151.bin
40d412dd694312269786b8cfe1448af1d7e7fc3267bb4150f30b55f9209bbef5
pdf-font-stream PDF embedded font (sfnt) at offset 0xE151 9580 bytes