Malicious PDF — malware analysis report

Static analysis result for SHA-256 52cf35961b6df9a9…

MALICIOUS

PDF

76.3 KB Created: 2021-09-16 21:29:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 20ba27e7380f0431e0ca7cc0b5e7794f SHA-1: 9acdb5319370029258ff2252ab69c6de7247fda6 SHA-256: 52cf35961b6df9a9a39aa823ab70f6b9751665762ce7fd6362ce464d3f929d5c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by a machine learning classifier and ClamAV. It contains numerous embedded URLs, many of which are part of a link farm designed to redirect users to potentially malicious content, disguised as free software downloads. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to obscure the true destination through numerous small, disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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
  • 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://nomylo.ru/uplcv?utm_term=free+video+capture+software+for+android PDF link annotation
    • http://vidiniaibreketai.lt/userfiles/file/solunupawotukovunatola.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/75644411104.pdfIn PDF document text
    • https://silky.ae/images/bulk_images/files/nilinefupuzuwokabavagewi.pdfIn PDF document text
    • http://azseal.net/uploads/userfiles/file/65388565127.pdfIn PDF document text
    • https://twinslock.com/locktactyuma/userfiles/file/98358013796.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/eb15f8d8d7888210af1346625ec4ff7e/78780012474.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/161305851adbc6---zefewilamaruzuxusele.pdfIn PDF document text
    • https://acavacecio.it/userfiles/files/46319302167.pdfIn PDF document text
    • http://w.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/jibomenewatapez.pdfIn PDF document text
    • http://huefpdf.org/upload/file/27196149751.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/tirobalokazisa.pdfIn PDF document text
    • http://abwingsjanaf.com/uploads/files/73471899541.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/45642530515.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/bemenoxafarusekam.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210911011329.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sadagelulabofojarobifoko.pdfIn PDF document text
    • http://video-cycling.de/files/file/84422411381.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///45358632720.pdfIn PDF document text
    • http://christopherdallo.com/file/53671106348.pdfIn PDF document text
    • https://leciv.fr/uploads/FCK_files/file/11028956515.pdfIn PDF document text
    • http://foodzipo.com/uploads/userfiles/files/xaxiwodapuwukel.pdfIn PDF document text
    • https://sleepthai.com/piceditor/file/zerokegu.pdfIn PDF document text
    • https://orsam.org.tr/paketler/ckfinder/dosyalar/files/91756618958.pdfIn PDF document text
    • http://vanprodukt.cz/UserFiles/File/bapogowogimepavedu.pdfIn PDF document text
    • http://wabasnb.com/files/fckeditor/file/14769733896139c16e4f973.pdfIn PDF document text
    • http://ainut.fi/userfiles/file/62401650554.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c7f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7F3 16504 bytes
SHA-256: ad5a6f38d1940c09496dd840d26e04e510220a2e7229bfad0a7756e27f1d6711
font_01_sfnt_off0000f224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF224 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3B 10796 bytes
SHA-256: 379ee302d9ddc7236321983fae890b5e988556ef3fb0f30b479b61cba61e0272