Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6109079a155868b…

MALICIOUS

PDF

84.7 KB Created: 2021-09-14 07:26:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 82b10ad85513ee30b5a0391d0b91004a SHA-1: 8eaf38e50b637058d15c32bc97cd50f1c35b41a3 SHA-256: a6109079a155868bb236f7d1163f9a9bfb7bc82240d7eea98d79da2a6362bff1
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm to distribute further malicious content or phish users. The presence of multiple external URIs and a link farm heuristic strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://mebizstekla.ru/userfiles/file/21061053058.pdf In PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/3b451f66d2983ac52f4e562e2107676c/sutorigetezunebosexaxok.pdfIn PDF document text
    • http://xnucleus.com/members/member_images/files/32448999066.pdfIn PDF document text
    • https://heyratacademy.ir/file/dubipa.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/15340110194.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/73860124776.pdfIn PDF document text
    • http://namjapizza.com/app/webroot/files/54637517694.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/lirewalekedifufuk.pdfIn PDF document text
    • https://www.cosanuesa.com/componentes/editor/ckfinder/userfiles/files/bazunojafifadep.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/maxapirulaje.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/67574062668.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210913034900679600pvr3w547yd9i.pdfIn PDF document text
    • http://alhegazgroup.com/userfiles/file/jezobowironope.pdfIn PDF document text
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jugodijetosizedudikimuni.pdfIn PDF document text
    • http://twapp.freshkon.com/upload/files/4112990786.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/98412937763.pdfIn PDF document text
    • http://antasboru.com/guvennet/resimlerfiles/xumelofixibimojunuguk.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132190b55008---61473304935.pdfIn PDF document text
    • http://berbun.com/user_img/file/39487379506.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.com/ckfinder/userfiles/files/82603460278.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/nu72r87va9dp70vh1bv3lipcjf/32369422095.pdfIn PDF document text
    • http://zeci.nl/im/image/fulijonapidofuvuzinirad.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/55598021578.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3bbe1d400---28565899548.pdfIn PDF document text
    • http://support-cmu.com/filedata/file/18472065829.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=minecraft+2020+app+downloadPDF 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_off0000e4bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4BB 10768 bytes
SHA-256: 462d32071b25805971bbc2e2c36c5148d71774ab28a98c7284312e4d09a3d0b2
font_01_sfnt_off0000fdb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB4 18384 bytes
SHA-256: 9623e052b68c7b104d4db97482bad2526e180b7c2550ecc6a15d44485c339480
font_02_sfnt_off00012cbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CBE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1