Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2315ed7981ae64f…

MALICIOUS

PDF

79.2 KB Created: 2021-03-24 09:51:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: eb72cec42f9afddb3609dc16adb13207 SHA-1: 9af6e0a3b41e4c7656d2439a7a0046d77ac5faf9 SHA-256: a2315ed7981ae64fc76efc2e089e9eb9f8b88658399dcb4fd1a223f22969aa2b
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 hosted on disposable domains, suggesting a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://jacksth.ru/award?keyword=business+ownership+structure+pdf PDF link annotation
    • https://mulokigapasol.weebly.com/uploads/1/3/1/0/131070847/dijedujul.pdfIn PDF document text
    • https://cdn.sqhk.co/suwezuzifu/RDnrIKZ/bronze_age_comics_key_issues.pdfIn PDF document text
    • https://cdn.sqhk.co/tevunufoba/tjgwhdW/touchbeat_drum_game_drum_set_drum_lessons.pdfIn PDF document text
    • http://tublitalia.space/30920416645sihyk.pdfIn PDF document text
    • https://dotofufodil.weebly.com/uploads/1/3/5/3/135313806/pazojadosidak.pdfIn PDF document text
    • https://meremunodimabak.weebly.com/uploads/1/3/4/5/134516451/a4b669c281f35.pdfIn PDF document text
    • https://cdn.sqhk.co/famazipow/4jiyii2/gumojimevuzosexizifali.pdfIn PDF document text
    • http://idealicaitaly.site/nuxurepovubunawemenewfhgr.pdfIn PDF document text
    • https://kumuxulunewun.weebly.com/uploads/1/3/0/7/130775174/nagigosivobigug-mulam.pdfIn PDF document text
    • http://whitecheat.xyz/nanesinagigikawulhneqy.pdfIn PDF document text
    • https://cdn.sqhk.co/rujamuzizogo/jehhuJB/girl_war_z_hack_online.pdfIn PDF document text
    • https://cdn.sqhk.co/rugugojeba/idicRQQ/feasibility_report_construction_example.pdfIn PDF document text
    • https://cdn.sqhk.co/lafuwexale/aRoGjeS/newodudabiwigoduki.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/2412f5d0-e2f1-4a93-99d7-5867e0142a9d/15262489103.pdfIn PDF document text
    • https://s3.amazonaws.com/fibesezati/heating_curve_calculations_worksheet_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/68d80d54-ed0f-4db3-a92f-a8796457df5b/como_hacer_un_archivo_con_varios_documentos_escaneados.pdfIn PDF document text
    • https://s3.amazonaws.com/bidivo/ruxizapelil.pdfIn PDF document text
    • https://s3.amazonaws.com/jiwisigetizoxif/pupavuwulabur.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6cb132ef-742e-4c9b-b629-2652944258b1/62165502270.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e028a597-6d43-433a-90fc-904823e75d24/can_you_get_ripped_with_trx.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/89c610cb-15b2-423d-aacc-4fcf38a34922/gps_essentials_manuale_italiano.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_off0000ed1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED1B 5024 bytes
SHA-256: d59357f995e4e4a29c9cabefd9e8d50347567ffefd24382d60fdc686df70d5db
font_01_sfnt_off0000fe3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3A 10136 bytes
SHA-256: 87a22f3f826d3dc32a5e913e019c52fed84f0c87de9929f92007a88b2f85510f
font_02_sfnt_off000120e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120E3 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c