Malicious PDF — malware analysis report

Static analysis result for SHA-256 f05fcc7ca184775f…

MALICIOUS

PDF

91.4 KB Created: 2021-10-22 21:36:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: d3351156d31fa6dea93d2f23311d7fa0 SHA-1: edbd6a796c513a4d3f56149ff608e4a91a726986 SHA-256: f05fcc7ca184775f2fec9cea1c1ccfa50ed841220b9eb5a1ef4fdbe63cf932e9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate it's designed to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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 http://tpt.taipei/asset/uploads/files/20921740217.pdf In PDF document text
    • https://investincarpathians.eu/app/webroot/media/files/viwosobukubofusiwuw.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/sipusi.pdfIn PDF document text
    • http://cmorshomecareassociates.org/uploaded_files/userfiles/files/59393289861.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/7ec8df3ea09fe4348f61a2d3a6b3264b/27539469779.pdfIn PDF document text
    • http://cieplej.pl/imgturysta/file/dozejadakuxuxije.pdfIn PDF document text
    • http://hasanmasat.com/ckfinder/userfiles/files/pobuwumaz.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/71649415799.pdfIn PDF document text
    • http://caffepontoni.com/uploads/file/gofisime.pdfIn PDF document text
    • http://35ct1.com/images/ckImageFiles/files/99346987530.pdfIn PDF document text
    • https://www.zochrot.org/ckfinder/userfiles/files/kolazerosite.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/5663095353.pdfIn PDF document text
    • https://gemma.lucien-sv.info/uploads/files/615f75c3680ea.pdfIn PDF document text
    • https://ijp2.com/contents/files/46085547282.pdfIn PDF document text
    • https://auto826.com/uploads/files/50473548438.pdfIn PDF document text
    • https://citrasas.com/userfiles/file/54237476565.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614487505bce7---bokazofejakokigipejar.pdfIn PDF document text
    • http://pietrek.com/MARCUS/files/file/movipusasejarinitimufen.pdfIn PDF document text
    • https://satesayap.com/contents/files/rinubesi.pdfIn PDF document text
    • http://podlahyadvere.sk/editor_uploads/system/files/metalipe.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/34024125537.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/90358051066.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/dedol.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/D9plVHj2VOU/uplcv?utm_term=what+is+dinosaur+reading+answersPDF link annotation
    • https://mediaget.com/userfiles/files/mefulijaroxugo.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_off00010087.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10087 18260 bytes
SHA-256: 9a03db4895470e94393ebee7ae318f753ecaa7edeae0278e6d8d676d6636652e
font_01_sfnt_off00013013.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13013 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001482a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1482A 10660 bytes
SHA-256: 7118b7c775a6423944451fc9cd265195666a22eb206dbfb7f4d9430f92d798be