Malicious PDF — malware analysis report

Static analysis result for SHA-256 a111960e9ce2dbf1…

MALICIOUS

PDF

81.5 KB Created: 2021-09-22 17:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d8db487978717d4eb47429b95c7ddc5d SHA-1: e1a2bd120528987d1eafd9b3f191e1ea015d7679 SHA-256: a111960e9ce2dbf1d06df36e36dbdfd00f3d018081278b1872857b86ac3653d1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF that contains numerous embedded URLs, many of which point to disposable domains. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://musikkursus.dk/userfiles/file/fozatixowozisadagame.pdf In PDF document text
    • https://eltechma.com/zdjecia/fck/file/sepatupefazafef.pdfIn PDF document text
    • http://prasongp.com/file_media/file_image/file/depaleliwiwawojifof.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/9be1ab07fccae59d0a9016e40c70c8bc/katevuzanatumadix.pdfIn PDF document text
    • https://pepsima.biz/files/file/mopakefobisoliravap.pdfIn PDF document text
    • https://susta.vn/userfiles/file/gujeb.pdfIn PDF document text
    • http://cataga.de/beta/files/file/xusojexasepituki.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/mofutomopodudosisuvo.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210919162750.pdfIn PDF document text
    • https://marikakozmetika.hu/editor_up/47444740463.pdfIn PDF document text
    • http://thaifilmind.com/UserFiles/file/66741347607.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/nofewa.pdfIn PDF document text
    • https://goldenlinejsc.com/userfiles/file/44217669299.pdfIn PDF document text
    • http://dautuck.com/uploads/userfiles/file/99548172250.pdfIn PDF document text
    • http://thebankcardservice.com/uploads/files/dapuj.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e209b04593---47785014678.pdfIn PDF document text
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/26681607937.pdfIn PDF document text
    • http://attlas.center/userfiles/file/76506392286.pdfIn PDF document text
    • https://thietbigas.net/media/files/reteranibew.pdfIn PDF document text
    • https://cubic.is/userfiles/file/debanexavasofazu.pdfIn PDF document text
    • https://posh.hr/files/92572577289.pdfIn PDF document text
    • https://sreekanakananda.com/ckfinder/userfiles/files/38420721542.pdfIn PDF document text
    • http://lidaoxc.com/upload/files/1651164087.pdfIn PDF document text
    • http://khachsansapa.vn/webroot/img/files/10796119235.pdfIn PDF document text
    • https://edenestates.com/ckfinder/userfiles/files/20077499045.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/26121089167.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=pawandeep+rajan+the+voice+of+indiaPDF link annotation
    • 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_off0000dac0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC0 10788 bytes
SHA-256: f92711668353264e0ba0807cdd8582340cfecf55c3dae1ab6bc40871c9b7cb26
font_01_sfnt_off0000f38b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF38B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B9D 17288 bytes
SHA-256: 5bba5470b80da0a959619a841bdf056c2c378f0acdd46fe4b96c4830f95c66ab