Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8d147327a93e94e…

MALICIOUS

PDF

77.5 KB Created: 2021-03-05 09:57:58 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 78d9cf6213441e34d15d37242a0cc835 SHA-1: 8d87fb8062dad237b74050055a4eedd5b277004f SHA-256: a8d147327a93e94e2bbb25463897fbf5d75212ef79a5c8fdda54c8ac22d39497
184 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, specifically flagging it as a redirector to malicious infrastructure. The embedded URL `https://dafemum.ru/strik?utm_term=anker+a7908+portable+bluetooth+speaker` is a clear indicator of a phishing or scam attempt, disguised as a product link. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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 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/strik?utm_term=anker+a7908+portable+bluetooth+speaker In PDF document text
    • https://static.s123-cdn-static.com/uploads/4380090/normal_6003143f5729c.pdfIn PDF document text
    • http://mumolazesinidix.getenjoyment.net/jojuv.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392873/normal_5ffa130cc3cdc.pdfIn PDF document text
    • http://zaxevef.getenjoyment.net/12271921784.pdfIn PDF document text
    • http://umkatrade.ru/skyrim_ps3_mods_installieren_germanc8s7z.pdfIn PDF document text
    • http://wdd13.ru/3rd_grade_reading_books_online_free1wypi.pdfIn PDF document text
    • http://naturagrush.space/mumenet99dls.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447640/normal_60340be2c7683.pdfIn PDF document text
    • http://theboldpantsproject.com/kanifofudami542yo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4492272/normal_60352cd1aa493.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://0dea665b-aaaa-42f3-a52c-f86f0fd1efa2.filesusr.com/ugd/8b9728_11a0bdc9c2c144e783e9034c80149d6f.pdf?index=trueIn PDF document text
    • http://nununad.myartsonline.com/rekizupavebak.pdfIn PDF document text
    • https://f405dec1-7f90-4f4c-a861-5286f67d0127.filesusr.com/ugd/ab922d_4880a06ee1994a7a98ce41385112d67c.pdf?index=trueIn PDF document text
    • https://5e0c4d4d-41f9-428c-9564-b93e7cff6769.filesusr.com/ugd/510691_54f20f4180224de4a00448ea8588fc38.pdf?index=trueIn PDF document text
    • https://7afcd0b8-98df-42a4-afe0-9544d44c9539.filesusr.com/ugd/74e9cf_a3f1f47456c441f8ad3361a79e6156fe.pdf?index=trueIn PDF document text
    • https://3e80c8bf-0031-4ca1-bfa9-4484641fefed.filesusr.com/ugd/08103e_3b900c85adb84c21bf74490f04f326a7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sugowubuf/what_is_uniform_acceleration_and_retardation.pdfIn PDF document text
    • https://91e55214-10ad-44cf-a10a-60a9392df58b.filesusr.com/ugd/e1c37d_df72f408e90c451eb34ab42512d9f57e.pdf?index=trueIn PDF document text
    • https://204833c8-abda-4421-8777-5048ee7dd919.filesusr.com/ugd/e30b7a_0d8b2dca465d4956af59c559c60e6d43.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fekife/36606525500.pdfIn PDF document text
    • https://s3.amazonaws.com/tuxexi/educating_psyche_ielts_answer.pdfIn PDF document text
    • http://palelezugob.onlinewebshop.net/rhythm_strip_interpretation_for_nurses.pdfIn PDF document text
    • https://s3.amazonaws.com/nuvukivaxiren/69455196240.pdfIn PDF document text
    • https://s3.amazonaws.com/jivamubug/xabimusatunulabinefusito.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_off0000ef59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF59 5672 bytes
SHA-256: 4964b813495e896eae0b86be8e985db8918d2616ce2aae4c156e07f0c8f0f936
font_01_sfnt_off0001029d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1029D 11008 bytes
SHA-256: e7dcf2ecc6091b3ab9ba1e14a42672296fbd6e817db668dbfbd20a0dd3ad4ed5