Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1b7b6e1b11eca6d…

MALICIOUS

PDF

80.0 KB Created: 2021-03-29 16:19:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 739ca8df3af331875b360349c72ed893 SHA-1: 23cb885c8d0b57d47846da8b179abbac0fba0046 SHA-256: a1b7b6e1b11eca6d368da500cfe49d9b8db669a4e351757ae1b3607a82ccee0d
244 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and a machine learning classifier, indicating it is likely a phishing or spam document. The presence of numerous embedded links, many pointing to disposable hosting and redirector infrastructure, suggests a link farm designed to distribute malicious content or lead users to phishing sites. The ClamAV detection further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/award?keyword=business+writing+test+pdf In PDF document text
    • https://cdn-cms.f-static.net/uploads/4425504/normal_605b25bd5ff19.pdfIn PDF document text
    • https://cdn.sqhk.co/xasexuwosul/iejgKib/38199406135.pdfIn PDF document text
    • https://cdn.sqhk.co/wupofolizaj/hgfYZeo/3940201940.pdfIn PDF document text
    • http://vonokumi.iblogger.org/bosch_-_800_series_24_built-in_dishwasher_with_stainless_steel_tub_-_black_stainless_steel.pdfIn PDF document text
    • http://xuzerujagojagip.scienceontheweb.net/craftsman_16_inch_38cc_chainsaw_parts.pdfIn PDF document text
    • https://cdn.sqhk.co/sokogiki/iehcNie/kivefulewenedogowut.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384029/normal_601701805491f.pdfIn PDF document text
    • https://cdn.sqhk.co/texekikevow/ihhjifW/prepaid_pocket_wifi_globe_promo.pdfIn PDF document text
    • https://watagejikifawup.weebly.com/uploads/1/3/4/5/134589749/d464609de.pdfIn PDF document text
    • http://jepegupunu.mygamesonline.org/verizon_voice_remote_volume_not_working.pdfIn PDF document text
    • https://cdn.sqhk.co/vuxesojogugu/YibmXja/nitosugov.pdfIn PDF document text
    • https://cdn.sqhk.co/nugizape/hbGdx82/45928557249.pdfIn PDF document text
    • http://nokasosozigof.mypressonline.com/65195628578.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404969/normal_605d7affba6f1.pdfIn PDF document text
    • http://ramuwesitavoz.mywebcommunity.org/poultry_farming_business_plan_download.pdfIn PDF document text
    • https://warajepujevofi.weebly.com/uploads/1/3/1/8/131857140/lagumadare-sagogukufexe-kigigako.pdfIn PDF document text
    • https://nexudusuje.weebly.com/uploads/1/3/0/7/130740550/merikixedoj.pdfIn PDF document text
    • https://sitimewodojex.weebly.com/uploads/1/3/1/8/131856527/bb70320057654ee.pdfIn PDF document text
    • https://refiraledekire.weebly.com/uploads/1/3/4/7/134715744/dceb18b53f3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4468536/normal_5fcf1267ce738.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://lilivuxaja.rf.gd/before_we_go_book.pdfIn PDF document text
    • http://bugazepoja.onlinewebshop.net/hp_deskjet_2541_all-in-one_printer_copier_scanner.pdfIn PDF document text
    • http://kifavudufolafu.epizy.com/how_to_scale_full_screen_in_windows_10.pdfIn PDF document text
    • http://wedizakur.epizy.com/xiliwisilejixorawajitil.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_off0000fc04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC04 5108 bytes
SHA-256: 19483a528829460370059d2f8f6cf5604af16d893153e5171df64a423b830b79
font_01_sfnt_off00010d92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D92 10900 bytes
SHA-256: 3a9e2732b92f1608bd0e0e5aa4c049021f40ca0e7b6297309efd5ab031a23a3b