Malicious PDF — malware analysis report

Static analysis result for SHA-256 af387bcd3b1682aa…

MALICIOUS

PDF

81.8 KB Created: 2021-05-07 21:57:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 08f1f563003fbe6c33cdf7d0092989fd SHA-1: 10b8c9c0b5c98579143789346f022a48ddf28512 SHA-256: af387bcd3b1682aab888957e458cc0670bed20d7fc409962fedafb241c57ddad
126 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it contains external URIs and functions as a link farm. The embedded URLs, such as https://midufefew.ru/strik?utm_term=the+veil+norfolk+dog+friendly, are likely used to redirect users to phishing or malware-hosting sites. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest an attempt to exploit users through malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 5

  • 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 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=the+veil+norfolk+dog+friendly PDF link annotation
    • http://dkblogin-de.com/zuxijeba3ct23.pdfIn PDF document text
    • https://cdn.sqhk.co/lipetebo/gcijjb6/paper._io_2_unblocked_free.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465131/normal_5fd7d1657aa52.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483362/normal_5ff8ad2767ee3.pdfIn PDF document text
    • http://guwajokuxo.22web.org/enclose_porch_with_plastic_sheeting.pdfIn PDF document text
    • https://cdn.sqhk.co/nemuvefik/gijeheT/arcane_quest_3_mod_apk_1._6._1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413012/normal_6058498fec3b1.pdfIn PDF document text
    • http://sreda.city/sphere_michael_crichton_sparknotess0ad7.pdfIn PDF document text
    • https://cdn.sqhk.co/rosivapixove/ccXhagh/tiny_beaded_tennis_bracelet.pdfIn PDF document text
    • http://gatorama.space/dell_studio_540_motherboard_specslebp6.pdfIn PDF document text
    • http://natlab.ru/salexokitamifuzuwum6n2x4.pdfIn PDF document text
    • http://bovuwitinix.22web.org/mawasanimotir.pdfIn PDF document text
    • http://cocobuka3.xyz/how_to_take_cover_off_ingenuity_bounceryon4a.pdfIn PDF document text
    • https://cdn.sqhk.co/dodagirojep/Ygugfvo/dafakan.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499283/normal_5fe8731f951d8.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/1634df29-e8bc-416b-8762-f44acde6ee72/nikon_p510_price_in_pakistan_olx.pdfIn PDF document text
    • https://s3.amazonaws.com/wokesabisevo/79636320574.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b51341d4-7aee-4768-8fd9-a62768a5e2c1/21521137441.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0242455d-ee62-4143-b481-74ff57cb3cbd/30925806963.pdfIn PDF document text
    • http://fobewejidopiwu.rf.gd/95226471962.pdfIn PDF document text
    • https://s3.amazonaws.com/rupatojuko/how_to_start_a_home_bakery_business_in_north_carolina.pdfIn PDF document text
    • http://fakulolipokate.epizy.com/campbell_hausfeld_electric_pressure_washer_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/nokiva/lilub.pdfIn PDF document text
    • https://s3.amazonaws.com/galinikagopit/harvest_moon_back_to_nature_guide_walkthrough.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8999c750-8483-47da-a2ba-826b1f70f1df/50364962544.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f26f0a4c-da94-4be2-8cff-db51eab2379a/blank_100_multiplication_chart.pdfIn PDF document text
    • https://s3.amazonaws.com/sajatesawodiji/biology_degree_planning_sheet_maryville.pdfIn PDF document text
    • http://buvudateba.epizy.com/juwesom.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_off00010227.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10227 4956 bytes
SHA-256: 7203a47c326eb8567030d082132eb395684f20f88cc3f326bf3b7567c70b3eb0
font_01_sfnt_off0001130a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1130A 10908 bytes
SHA-256: dfc38221efe96d4d47489f3cc8167ee9a34bb9b7454fb83aa0b88d130bb69d68