Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b4e328c5950bd50…

MALICIOUS

PDF

70.1 KB Created: 2021-09-27 11:32:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ee6e17aaaae29989e9e85fe995592380 SHA-1: b36448bf743b0cc3549794155449faec295ab13f SHA-256: 8b4e328c5950bd50b737c336ebee0633cf487e1da231d98e2a85c46531014073
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external links, including one to an algorithmically generated URL, suggesting it is designed to redirect users to malicious sites or download further payloads. The PDF is also identified as a link farm on disposable hosting, reinforcing its role in a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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 link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://poslovniimenik.net/firme_data/files/54088606670.pdf In PDF document text
    • http://vektor-bezpeki.com/userfiles/files/37456737886.pdfIn PDF document text
    • http://bienbao.org/uploads/files/jekivonisesujejazokuwo.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/70769205087.pdfIn PDF document text
    • http://viquadro.com/userfiles/files/38876540607.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/31699212293.pdfIn PDF document text
    • http://aurora-c.jp/files/files/8590302323.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/pukupogikamisizurilis.pdfIn PDF document text
    • http://bluecreator.biz/ckfinder/userfiles/files/76316933535.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/mugixuko.pdfIn PDF document text
    • https://www.hkha.org/ckfinder/userfiles/files/woxulazabuzi.pdfIn PDF document text
    • http://tpokebar.com/uploads/files/43349539068.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/26333057649.pdfIn PDF document text
    • https://romalasergroup.com/userfiles/files/ragudazevu.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/vifoxanumizutisux.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210925212603.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/65832950454.pdfIn PDF document text
    • http://uslugi-ogrodnicze.pl/pliki/File/moxinufitif.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/26959632626.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16142ac165a750---27475805604.pdfIn PDF document text
    • http://ed-union05.ru/files/file/genulubufosatevobeg.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/dapedulenamoxevomonarag.pdfIn PDF document text
    • http://futsalcb.cz/picture/vtextu/file/wizavizuwap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+set+bold+text+in+androidPDF 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_off0000ae34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE34 10560 bytes
SHA-256: 28b744b2e0d8e72646a2d3c923d68aa2fc0169463bbe996bdc8f776e673ac64d
font_01_sfnt_off0000c66c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC66C 17112 bytes
SHA-256: 6a34208f4296056f5b540e673727eb6c3c2c7ff697e557791089b920dafad953
font_02_sfnt_off0000f309.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF309 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1