Malicious PDF — malware analysis report

Static analysis result for SHA-256 8396019a19370f3e…

MALICIOUS

PDF

82.0 KB Created: 2021-09-21 14:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: f11d1066c881859947c80f288d22ce06 SHA-1: 6aab1841c71582ec5da37dadbfcf40b344a31d3d SHA-256: 8396019a19370f3e5ec41015bd8369aacb52331258d5bfaa5a216af044ffb62a
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, presenting numerous links to other PDF files hosted on disposable domains, with a specific heuristic identifying it as a 'PDF_SEO_DISPOSABLE_LINK_FARM'. One of the embedded URIs points directly to an IP address, which is a common tactic for obfuscating malicious destinations. The overall purpose appears to be to redirect users to potentially harmful content or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://roberlo.cz/www/files/file/fukureporas.pdf In PDF document text
    • http://smolninskayahotel.com/userfiles/file/kixomotozarololiti.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/9328848191.pdfIn PDF document text
    • http://www.yankey.com.tw/demo/public/editor/ckfinder/upload/user_upload/files/wowolexewifapomefisuteb.pdfIn PDF document text
    • http://namkhoabacninh.com/images/files/23186015937.pdfIn PDF document text
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/5142605231.pdfIn PDF document text
    • http://arabstina.com/ckfinder/userfiles/files/winugelarupexumavamosojo.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/zisamawuralixasozejatowe.pdfIn PDF document text
    • http://kamienneogrody.com/userfiles/file/49486096271.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/xodujivajobew.pdfIn PDF document text
    • http://mywymc.com/userfiles/file/rifizowimosofetigujaleke.pdfIn PDF document text
    • https://wotfiles.com/ckfinder/userfiles/files/lasonajizusavil.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/ea995bef8d212b034473bb571d848aab/61802719273.pdfIn PDF document text
    • http://185.33.116.142/~bbyacht01/upload/files/69023840714.pdfPDF link annotation
    • http://netichikawaya.com/userfiles/file/bilupiwilemekuxunaweguw.pdfIn PDF document text
    • http://gonzagafood.com/userfiles/files/joribetidodiratusekoveje.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/32480386923.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wozedazuwegefe.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/pigemusatemobux.pdfIn PDF document text
    • https://granitnet.hu/editor_up/butowujotejejifowa.pdfIn PDF document text
    • https://kentacademymiango.com/userfiles/file/92857512412.pdfIn PDF document text
    • http://gesht.ru/admin/ckfinder/userfiles/files/toxolixupijelede.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/nesamigitubuxaw.pdfIn PDF document text
    • https://lifesmart.ro/ckfinder/userfiles/files/rumelavowuxagaralufagaz.pdfIn PDF document text
    • https://trsoftyazilim.com/genelresimler/file/2561151091.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=download+game+robbery+bob+modPDF 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_off0000ddb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB3 17460 bytes
SHA-256: adb4dbd49463fd3c4eaf0bfe7bdab7fbfb6d6324fdf1de53010eff98c86781e1
font_01_sfnt_off00010a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12259 10572 bytes
SHA-256: 0885ba4b424f9e3756fb37837e5bbad6bd39f34ccdac02fff0a2c865af49471e