Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f75898a4e9611f1…

MALICIOUS

PDF

69.4 KB Created: 2021-09-05 11:21:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8b9a0707edf5913523462202ceca0585 SHA-1: 4e2e615064be81c3765be2cf17a1c0b24840712a SHA-256: 4f75898a4e9611f121c8146fb77f9bf2b31b7f69168e5dd4f7c98fd69b53eab7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of external URIs and link farms suggests an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://drafthe.ru/uplcv?utm_term=capgemini+pseudo+code+pdf PDF link annotation
    • http://esoftland.com/userfiles/file/50733246924.pdfIn PDF document text
    • https://gullyracing.it/admin/ckfinder/userfiles/files/tinoborulawiwezezopib.pdfIn PDF document text
    • http://mellorymotors.ru/admin/ckfinder/userfiles/files/gaginajoj.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/e7aa0fedd17f02d6890c38bd1838e7e9/wavofupaga.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125321a3ba54---zexupubidamunaferi.pdfIn PDF document text
    • http://fonnepal.org/userfiles/file/vupisinumu.pdfIn PDF document text
    • http://skybuildinfraprojects.com/uploads/dafavetavij.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160af9fc9b6519---rajawobexowozemebiwuduf.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/lt9u6jdi2301psmnc96osame65/zavizemikovi.pdfIn PDF document text
    • http://plafondchauffant.fr//img/user/file/renamivebej.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/99333017568.pdfIn PDF document text
    • https://doxity.ro/ckfinder/userfiles/files/jixedo.pdfIn PDF document text
    • https://soudurelauziere.com/upload/editor/file/30879005375.pdfIn PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210720_183610.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/5m2uh3o6u71iio7f72rrnum2gg/xinobebe.pdfIn PDF document text
    • https://fasaac.org/temp//files/25956645184.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161106e35a533c---44704735831.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/198d8a10494b74ded7eba06ae4fa6d4a/zamumonisafilevoruf.pdfIn PDF document text
    • https://securityguardsupply.org/php/uploads/file/5420089517.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/t1422ceir2n442553ou87joqsg/kopis.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab0a192abf1---fazuwuwot.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16080e6d7d59cc---bozixututedugulosop.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132702f4dcfd---finuvenubinewolugiwiv.pdfIn PDF document text
    • http://www.perchegouet.com/ckfinder/userfiles/files/41686260883.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/50956215727.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b26e769f12---51593336094.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_off0000b3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DD 14428 bytes
SHA-256: 577b6e964a3582d608f8a7d16a8fe570285eade7204de341d4cff0b605ecf1d9
font_01_sfnt_off0000d739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD739 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF50 10852 bytes
SHA-256: e529e2f51832afa96b9a7aca58a2ce59ac1eaf2713912b227ab741af09417cc0