Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab3635129f7ba703…

MALICIOUS

PDF

77.0 KB Created: 2021-04-07 23:08:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 803043f853c809d5d81ed7f1f322788e SHA-1: 063749c78aec69fca1595db46659c62c19cb38f6 SHA-256: ab3635129f7ba703c63091171310da342b583bd93887a4a95bf642a31470fde4
166 Risk Score

Malware Insights

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

The PDF document is classified as malicious by ML and ClamAV, and contains numerous embedded URLs pointing to suspicious domains. The document body, though partially corrupted, suggests a lure related to purchasing a used car, which is a common phishing tactic. The presence of multiple disposable hosting links and redirects indicates an attempt to obfuscate the final malicious destination.

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://zajinet.ru/strik?utm_term=what+should+i+check+before+buying+a+used+car PDF link annotation
    • http://procripton.com/98678038595ypdq7.pdfIn PDF document text
    • http://ottics.ru/dagobuxegesit3oafx.pdfIn PDF document text
    • https://cdn.sqhk.co/diduwuposenu/ifKJLgg/horror_clicker_best_clicker_horror_games.pdfIn PDF document text
    • https://cdn.sqhk.co/webegodebav/gh5o9hd/rirebuxofasowexuti.pdfIn PDF document text
    • http://pubguckazan.com/2012_dodge_avenger_sxt_plus_sedan_4dlr04a.pdfIn PDF document text
    • http://masajsalonunuz.com/wibekuzanepalwojw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382771/normal_6052ffaa069a0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419851/normal_6068ca2e53704.pdfIn PDF document text
    • https://cdn.sqhk.co/limizolaxa/ojdmkgc/caracteristique_du_chat_american_curl.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474720/normal_60118f16e592d.pdfIn PDF document text
    • https://cdn.sqhk.co/wuvinudubuno/ehbjeia/mejizoxeturadisoxilifuf.pdfIn macro / runtime command snippet
    • http://mbfsopg.com/tegelileva73zvh.pdfIn macro / runtime command snippet
    • http://tosety.xyz/victor_frankenstein_movie_dual_audiog3b4k.pdfIn PDF document text
    • https://cdn.sqhk.co/dofexoxev/jcOgfhd/kizokolajiwumuxefi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474720/normalIn macro / runtime command snippet
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://f6e2a16f-d004-42cd-8f17-0463e090774c.filesusr.com/ugd/c70c35_7cf9824bf50245168c259522e3ae976a.pdf?index=trueIn PDF document text
    • https://8c77b9b7-c39b-43d6-9406-6086bd2c0f93.filesusr.com/ugd/ee6770_020cce3fbdab4233b492a5715ef677fc.pdf?index=trueIn PDF document text
    • https://a96990da-dd17-4b11-844c-aba2d588d1b6.filesusr.com/ugd/5e5e7b_9e83c2acb81241ef9354398462587bce.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/084d6b97-e5f0-4a81-8a8b-71b948592591/public_relations_specialist_salary_florida.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f18b194-556b-4f5d-b346-95b7152bd962/who_are_the_main_characters_in_the_christmas_carol.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_off0000eeb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB2 5604 bytes
SHA-256: a08c27e638cc1c9c9668827678b8391635e55858ea6540adc187afbfe29e5895
font_01_sfnt_off000101d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D2 10852 bytes
SHA-256: a36c98140b1e28108afca50aee3ff3f19557e622693b172e5d46239f018d7860