Malicious PDF — malware analysis report

Static analysis result for SHA-256 4624b8bfa4836d00…

MALICIOUS

PDF

80.5 KB Created: 2021-09-17 03:52:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ece26bc9812ebc81449d755cfc9d2314 SHA-1: e9e32d0f121f6ea6a97656d15b8211800b834002 SHA-256: 4624b8bfa4836d0059c820633ff632d5dbba20f3bd4f6c8ae8b7d1f93855ede3
156 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 links to external websites, several of which are hosted on compromised CMS uploads or disposable domains, suggesting a link farm or phishing lure. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicate an attempt to direct users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://huntic.ru/uplcv?utm_term=mirror+iphone+to+firestick+2020 PDF link annotation
    • http://rent-lease-no1.com/userfiles/file/20210907011039.pdfIn PDF document text
    • http://atreve.eu/ubezpiecz/obrazy/file/kukavikoziruzireterema.pdfIn PDF document text
    • http://rungrawin-itt.com/userfiles/files/kopedafuz.pdfIn PDF document text
    • http://qiuyutv.com/userfiles/files/20210916043353.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/gitinokutopaxarikezelo.pdfIn PDF document text
    • https://www.sonorisation-auxerre.fr/ckfinder/userfiles/files/fuvidewuvanegokawimataxif.pdfIn PDF document text
    • https://eagleegg5k.com/ckfinder/triplebuserfiles/file/fuwinuzerelakewozuvebezi.pdfIn PDF document text
    • https://gopherscopes.com/userfiles/file/mijugitodisim.pdfIn PDF document text
    • http://rsentco.com/upload/file/jutagijopotiwubujodadevi.pdfIn PDF document text
    • http://yongqingtech.com/d/files/51988420679.pdfIn PDF document text
    • http://avtokit116.ru/!upload/files/86597551606.pdfIn PDF document text
    • https://ketdoanbus.com/webroot/img/files/3925105047.pdfIn PDF document text
    • http://lightningriskassessment.com/ci/userfiles/files/25220141556.pdfIn PDF document text
    • http://noavarservice.com/ckfinder/userfiles/files/33466122218.pdfIn PDF document text
    • http://vaynhe.com/upload/files/guxisabutonubavadelujosuz.pdfIn PDF document text
    • http://kowalstwwo.pl/public/cms/images/file/49398072267.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/59025010267.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/2741a4e61d2bee98ecf57f5b20fea777/96319540470.pdfIn PDF document text
    • http://jawarakreasi.com/file/mebapalodubasugunuxus.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/8dddd0f54aeb6dcaa73ab53328edd941/gelumugudix.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/33228012853.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161394d0e8e14f---39332050987.pdfIn PDF document text
    • http://hangtatmj.com/userfiles/70622078133.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/dajebuvo.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_off0000d66e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD66E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE80 17504 bytes
SHA-256: d780f743ce761a83ffe5ab5431c8189a2925af7221e412d0f9a468e16f608cc0
font_02_sfnt_off00011bc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC1 10696 bytes
SHA-256: d82526d64141766b7edc2680257fb8cd41ce99a7b96b39de8af27a248053e933