Malicious PDF — malware analysis report

Static analysis result for SHA-256 bec8e6fa2b83a4c6…

MALICIOUS

PDF

78.9 KB Created: 2021-05-22 17:45:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 740350fde1e422c0a10a706c21272389 SHA-1: d6589bb423eec9656d79f36f4f78d6e01130e7b6 SHA-256: bec8e6fa2b83a4c68fcaf5e4cd696ea7cb0c54f185b18f73604e360f1aec469f
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many pointing to disposable hosting, and one primary malicious URL. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, suggests a lure related to a 'Cambridge quick placement test'. The presence of embedded URLs and the link farm structure suggest this PDF is designed to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://baarspo.ru/strik?utm_term=cambridge+quick+placement+test+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4385410/normal_604ccf963194a.pdfIn PDF document text
    • https://denosofebulapan.weebly.com/uploads/1/3/5/3/135347567/darup.pdfIn PDF document text
    • https://begobaxu.weebly.com/uploads/1/3/5/3/135336669/suvamaguweli.pdfIn PDF document text
    • https://boxatikavizag.weebly.com/uploads/1/3/4/6/134680825/gelevarexopoma.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383688/normal_603d7cc49f844.pdfIn PDF document text
    • https://fuzitadixasixo.weebly.com/uploads/1/3/1/3/131381677/dakegijixebuwog.pdfIn PDF document text
    • https://lobovalosidim.weebly.com/uploads/1/3/1/4/131437181/pobabifo.pdfIn PDF document text
    • https://zujomesesewega.weebly.com/uploads/1/3/4/9/134902804/d30c02ee8957.pdfIn PDF document text
    • https://rinapaluvubozi.weebly.com/uploads/1/3/4/6/134669605/jivaxap-gapafegidose.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478393/normal_6031c7e78e244.pdfIn PDF document text
    • https://fegedagupadid.weebly.com/uploads/1/3/1/8/131856554/womasetobijonifu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/28356e0c-39e5-41ba-9ccf-b79a2a518329/53878972903.pdfIn PDF document text
    • https://s3.amazonaws.com/jumedemimo/how_to_get_rid_of_pimple_marks_home_remedies.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d4bf9655-7323-41d9-b174-aa01d99a4e6e/rabitelofovikumikeke.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a15d39d-c5fd-4d95-895c-8ee402aac70c/how_to_fold_a_graco_pack_n_play_with_changing_table.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3d6c0ea6-e1e5-4758-b2bb-2d6f5f1484d6/where_to_put_tens_unit_pads_for_neck_pain.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/350624ca-3a29-43e2-881d-32a4c8f921be/9712198263.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6560a63-025f-4dd1-bcd9-00517d59c990/alto_sax_replacement_parts.pdfIn PDF document text
    • https://s3.amazonaws.com/fowikorejodi/easy_touch_system_indoor_control_panel.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e75b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE75B 5600 bytes
SHA-256: bf813e222f8a40d15efacaa718812ce2a7c4adfe37bf22411bec01b16acd6e33
font_01_sfnt_off0000fa49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA49 11644 bytes
SHA-256: a0ebfded387dddb4ff46160ef644415f231d77a3b85cd98d5e480cec3b52eff2
font_02_sfnt_off00012065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12065 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3