Malicious PDF — malware analysis report

Static analysis result for SHA-256 a27dcabb58c3ce1a…

MALICIOUS

PDF

72.5 KB Created: 2021-05-04 20:30:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 3df7ce22d5fe659f56444bf4b785afd6 SHA-1: 7d811429d79b177f42fc9481dca835d0b8c51b1c SHA-256: a27dcabb58c3ce1a261d89246effeea7d43f48dadee3517e8741070935de1dac
186 Risk Score

Malware Insights

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

This PDF file contains numerous external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, with the PDF_SEO_LINK_FARM heuristic identifying a mass of external PDF links. While no scripts were explicitly extracted, the nature of the heuristics and the embedded URLs point towards a phishing or malware distribution scheme, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://kuzutuzo.ru/strik?utm_term=how+to+rebuild+toro+lawn+mower+carburetor PDF link annotation
    • https://wezuzasiteva.weebly.com/uploads/1/3/1/3/131397996/fofogoge_puxulabesik.pdfIn PDF document text
    • http://indohealth365.online/one_clue_crossword_answers_chapter_40fag5k.pdfIn PDF document text
    • https://kukezuleji.weebly.com/uploads/1/3/4/3/134361302/rududokuvuwi_tipabinovex_roroberababor.pdfIn PDF document text
    • https://cdn.sqhk.co/wamitavixitu/KjctV6t/67896788926.pdfIn PDF document text
    • https://vugadeji.weebly.com/uploads/1/3/1/4/131406436/043a4b25c.pdfIn PDF document text
    • https://menufepu.weebly.com/uploads/1/3/1/1/131163725/raturu.pdfIn PDF document text
    • https://cdn.sqhk.co/tatidukigag/wrBjIgc/medazotanigumepufaf.pdfIn PDF document text
    • https://cdn.sqhk.co/bugabowozi/bMajejj/wolf_appliance_repair_seattle.pdfIn PDF document text
    • https://tisalupiruj.weebly.com/uploads/1/3/4/0/134018152/vixexuxu.pdfIn PDF document text
    • https://naziwimirup.weebly.com/uploads/1/3/4/3/134371197/nazazokazaxavo_risile.pdfIn PDF document text
    • http://about-fb-support.com/adding_and_subtracting_polynomials_activity_24_answers321p5.pdfIn PDF document text
    • http://genoray.pro/guy_de_maupassant_the_jewelry_analysis7g79u.pdfIn PDF document text
    • https://cdn.sqhk.co/fuwufupi/IibW0bS/jimedesepawopotuwulu.pdfIn PDF document text
    • https://cdn.sqhk.co/bewewojiwo/ijhSWh4/prepper_food_kits.pdfIn PDF document text
    • https://cdn.sqhk.co/kuwusemob/hgjfEja/pdf_annotator_free_portable.pdfIn PDF document text
    • https://jegivobepumo.weebly.com/uploads/1/3/4/4/134444156/bezawafovef_vunijiminusan_kuvefokesamufuf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7e574f8b-ef34-4833-8dee-b18f3ac9fc91.filesusr.com/ugd/af8ffd_76e9f31254924972b1372042861d523f.pdf?index=trueIn PDF document text
    • https://0315d410-4255-45a3-9477-873949dd02ac.filesusr.com/ugd/f85006_512f3f1e01dd4843934c12196c86f0ec.pdf?index=trueIn PDF document text
    • https://4ab51db4-2ab9-4ce7-8cf9-a7235cd4f8a6.filesusr.com/ugd/c6359c_c6245bd9423a4bebb604b830bbd15a55.pdf?index=trueIn PDF document text
    • https://d45de9d9-8116-4232-9203-1b9506c390e4.filesusr.com/ugd/a69a10_129b9a1b6fe04ade9d8316ba5c0dd147.pdf?index=trueIn 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_off0000dda8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA8 5100 bytes
SHA-256: 0fab4bdac15c1f1b014d627e8f6ff14a0d3fb1579328f42a0dbbc0ecb02daf04
font_01_sfnt_off0000eef7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF7 11152 bytes
SHA-256: 7981fcdc98a04d22331403346863517876e1c3048d7950aa3c2028bcc9b5b094