Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21972fa1be07b00…

MALICIOUS

PDF

78.4 KB Created: 2021-05-10 06:00:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 95d227de4d7a19b29f37ffb9ba40d704 SHA-1: 0c434f90849983c1f673297ba05e51c9f15cc431 SHA-256: b21972fa1be07b0061cdfa187cbc890f816abc5b17438a9c0f5fdcb08501077b
186 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning model assigned a high probability of maliciousness. Heuristics indicate the presence of a large link farm, with many links pointing to disposable hosting and utilizing UTM parameters, suggesting a phishing or SEO spam campaign. The embedded URLs and the nature of the heuristics 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://midufefew.ru/strik?utm_term=can+netherland+dwarf+rabbits+live+outside+in+the+winter PDF link annotation
    • https://zatikavetix.weebly.com/uploads/1/3/2/3/132303242/4540992.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4428331/normal_600f9dc83a58a.pdfIn PDF document text
    • https://cdn.sqhk.co/tatidukigag/gcJid07/62781748975.pdfIn PDF document text
    • https://zutafagufagupak.weebly.com/uploads/1/3/4/2/134235067/0160681fc7c3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459939/normal_5ffea8b4d3e92.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371814/normal_5fcd9fd867c4f.pdfIn PDF document text
    • https://gogujezirud.weebly.com/uploads/1/3/4/6/134655685/tagasok-gelukasipadowo-xozimipozolisa.pdfIn PDF document text
    • http://xujimutisep.iblogger.org/bsnl_broadband_plan_change_form_online.pdfIn PDF document text
    • https://cdn.sqhk.co/zisujidixa/1Mhf1nQ/paradise_island_hours_appleton_wi.pdfIn PDF document text
    • https://jevebuna.weebly.com/uploads/1/3/4/5/134594548/sojidinetiwudomoxu.pdfIn PDF document text
    • https://cdn.sqhk.co/nowovadizeb/hOjhqic/86538450168.pdfIn PDF document text
    • https://tozabofosizo.weebly.com/uploads/1/3/5/3/135340530/pifepaxaso.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366020/normal_5ff14b2772fc8.pdfIn PDF document text
    • https://cdn.sqhk.co/merabuvi/dgcii18/54925370653.pdfIn PDF document text
    • https://cdn.sqhk.co/vutexexukus/ejbeiaw/world_best_camera_app_for_android_download.pdfIn PDF document text
    • https://cdn.sqhk.co/jomutepe/bjcjhjj/cramped_meaning_in_urdu.pdfIn PDF document text
    • https://cdn.sqhk.co/goluxewimabu/cgehjha/lenovo_laptops_charger.pdfIn PDF document text
    • https://xajixaze.weebly.com/uploads/1/3/2/3/132302973/f285e0d114ce.pdfIn PDF document text
    • https://cdn.sqhk.co/zejejofe/jjryzJ3/learn_spanish_podcast_download.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://rapabilalame.rf.gd/sopolerazobatudaxukis.pdfIn PDF document text
    • http://petalewoxux.rf.gd/soxibof.pdfIn PDF document text
    • http://xamunenefo.rf.gd/renaissance_periodization_powerlifting_strength_template.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f581.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF581 5192 bytes
SHA-256: b6cd3e084121191e47247eab023a65d60c0cc381a61e44755215519ba6e456cf
font_01_sfnt_off00010736.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10736 10676 bytes
SHA-256: baea93a6470805463c4312837cc1e02a912c8f0c31addd6de60afdf3a9774aa5