Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a9c0cdb2987fb9c…

MALICIOUS

PDF

80.9 KB Created: 2021-09-16 17:48:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3328747d55840e835eedfd4dcba53481 SHA-1: a8c8d1822fff7ad750721d88269f17eb9a6d03ef SHA-256: 4a9c0cdb2987fb9c54c0ad135fd0fa9170cd81e5004c9d86a1938bb9cd360d8e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting it's part of a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://catamma.ru/uplcv?utm_term=local+keyword+generator PDF link annotation
    • http://oticonshop.net/ckfinder/userfiles/files/litaxifo.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/87585765855.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210910233456.pdfIn PDF document text
    • http://archgeo-leszno.pl/uploads/userfiles/files/lulegupo.pdfIn PDF document text
    • http://dmkert.hu/files/file/26654804631.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/57646524292.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/xefimururatutexapomegem.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/bajomerorupo.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/39394728383.pdfIn PDF document text
    • https://pecintajp.com/contents/files/3887727211.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/11371515678.pdfIn PDF document text
    • https://kemxoithanhhang.vn/app/webroot/files/images/pages/files/9504575654.pdfIn PDF document text
    • http://favorit.pl/userfiles/file/23055975209.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/duvanowajibot.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139805d298fa---buvafo.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614330ee02128---pinaluxuwirumuzalijid.pdfIn PDF document text
    • https://emons-verlag.com/testarea/cwsCMSlight/media/files/86495281027.pdfIn PDF document text
    • http://meubelenindex.nl/images/uploads/83727332418.pdfIn PDF document text
    • https://koparieshorvathbusz.hu/files/file/63512276426.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/19725298336.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/76176115817.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109071301431703.pdfIn PDF document text
    • https://cancelaria.pl/galeria/file/gapanefedafefaxa.pdfIn PDF document text
    • https://adikmanis.com/contents/files/lumed.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_off0000d972.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD972 17216 bytes
SHA-256: 96683df11ea0882c5d9dcbb82e763436ecba7e95f58ea3a82ddac9fdd55feb4e
font_01_sfnt_off000105b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B2 10536 bytes
SHA-256: 339ab295310ff082160cf91aa94e985b005e519c950b344a983ec5d6eef9d9c6
font_02_sfnt_off00011db5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1