Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cb92170c9097ac2…

MALICIOUS

PDF

70.9 KB Created: 2021-09-17 07:19:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 54ab2d86558c5ee4a161c36b9f137db7 SHA-1: 11952ea207b74381c23daade7e474f367ed46937 SHA-256: 3cb92170c9097ac2ae5bd69e839f2a5c78affccf5e43d1cf5b0f81502011ca2b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and is structured as a link farm hosted on disposable domains, indicating a probable phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and embedded URIs strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://medvor.ru/uplcv?utm_term=boot+animation+creator+apk PDF link annotation
    • http://dental-forum.ru/userfiles/file/96468219720.pdfIn PDF document text
    • http://www.cerathai.com/image/upload/File/47171653308.pdfIn PDF document text
    • http://kurier48.pl/files/userfiles/file/2520116057.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/zesirudipejuz.pdfIn PDF document text
    • https://gdaniec.com/upload/files/82695746102.pdfIn PDF document text
    • http://perksys.com/userfiles/file/manesodoli.pdfIn PDF document text
    • http://commandhousecreations.com/uploads/files/tenadaruverawodoxibipuja.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/72985863254.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202109161700031635.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/9879390713.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/8320759699.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/68186147104.pdfIn PDF document text
    • http://ingegnasrl.com/userfiles/files/fuzivukeligalip.pdfIn PDF document text
    • http://guowangcable.com/d/files/tasedas.pdfIn PDF document text
    • http://kocavietnam.com/upload/files/47390197950.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/bivasulumafexikanosaxoten.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/zowizubofof.pdfIn PDF document text
    • http://aotwresort.net/ckfinder/userfiles/files/47147934131.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/87417062351.pdfIn PDF document text
    • http://status.cz/UserFiles/File/torupi.pdfIn PDF document text
    • http://tiszaikaland.hu/upload/file/89390814920.pdfIn PDF document text
    • https://zlataraburmevuckovic.com/files/fizuvuz.pdfIn PDF document text
    • https://onderhoudnlgarantie.nl/upload/file/jozutojozatowujom.pdfIn PDF document text
    • https://sealordhotels.com/ckfinder/userfiles/files/gitijogopaza.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/31108543250.pdfIn PDF document text
    • http://korea-labels.com/ckfinder/userfiles/files/lasedejigudud.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_off0000b64f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB64F 15756 bytes
SHA-256: e92833425ac9014f5f188a632456b8adf510be50446879296f8a135daaa8829d
font_01_sfnt_off0000de32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF649 10468 bytes
SHA-256: baeff6d09a3928839ca9fea91cce1ea295eb36a3575e6daf8c5f1c1f992b8ebb