Malicious PDF — malware analysis report

Static analysis result for SHA-256 537f5b669ea8eb0f…

MALICIOUS

PDF

94.8 KB Created: 2021-09-22 11:34:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d5a754c018043210edcb103028fe56e2 SHA-1: e353160aa43f04ff9917f13ee3ebedca57112c76 SHA-256: 537f5b669ea8eb0fa3e86813097698fa573909fc58edbed81ccdf538b7068653
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or scam operation. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://smidgel.ru/uplcv?utm_term=oxford+advanced+learner%27s+dictionary+apk+full+crack PDF link annotation
    • https://evermoral.hk/upload/file/1632125325.pdfIn PDF document text
    • https://www.lucaslobker.com/minor/ckfinder/userfiles/files/45322163790.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/funemajulutujakawewaxi.pdfIn PDF document text
    • https://dhins.com/testingsites/advantage_aviation/assets/media/file/fawuperiravisolego.pdfIn PDF document text
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/41820655178.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/bozapineladutexe.pdfIn PDF document text
    • https://cebrium.ssnn.ro/images/woxobonibuxulosamoju.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/26618009516.pdfIn PDF document text
    • https://www.jaegeraviation.com/ckfinder/userfiles/files/vixexon.pdfIn PDF document text
    • https://idosekotthonaveresegyhaz.hu/files/files/dederajafomi.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210909_103131.pdfIn PDF document text
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/86081588705.pdfIn PDF document text
    • http://terremeraude.com/userfiles/file/juxofupakojisaja.pdfIn PDF document text
    • http://www.leasebridge.com/CKUPimg/files/13357109891.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210914035655.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/moxugenelodatedixe.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161401ddd7c0ee---nifipov.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/bulupelevojekuja.pdfIn PDF document text
    • https://stl-log.com/htdocs/cljr/data/files/nasodunowodo.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/14261883339.pdfIn PDF document text
    • http://3t-t.com/User_File/UpFile/file/20210906101245_dmVmZXR1bm9m.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F0 23388 bytes
SHA-256: 83d4f4192c715386c754126692920d6bd68c5971c8d4f276a615957a8e389723
font_01_sfnt_off0001329f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1329F 11148 bytes
SHA-256: d451e1e5612420e94464db2f7b03b68c1881abe63f81cab0de2cab6ffc27fdc9
font_02_sfnt_off00014cef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14CEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000164fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x164FC 1680 bytes
SHA-256: 6c08887b596ecb472c5a0482df8c2f828d83fc5b5d16111ed0caa1fced1b35dc