Malicious PDF — malware analysis report

Static analysis result for SHA-256 df3852a5ac56ba2c…

MALICIOUS

PDF

73.8 KB Created: 2021-09-01 10:26:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f566bca92ed5a7fdb78d1d96a342d7c7 SHA-1: 47c036e28076939c8c003ec05562b1c601ffc645 SHA-256: df3852a5ac56ba2c6f22f8da04d32cc66d1dfe49c8126fce720867ea2db3cee6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for delivering malicious content. The PDF also contains numerous external URIs, many of which point to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious destinations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=sorry+seems+to+be+the+hardest+word+sheet PDF link annotation
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073172328c60---xularoletubibapulivupilat.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/tepoxenedip.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/f0e2954472a669160585b7f9bf259efc/xigoxiri.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/16205443955.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/8kdjg2umtg5440p690m4a55vn3/44576693983.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/jagb9basdn63uu8104rh05d7ob/83892264714.pdfIn PDF document text
    • https://embassyinvietnam.com/webroot/img/files/botibabegizosexu.pdfIn PDF document text
    • http://eastcoastbiker.de/sites/default/files/file/56310081530.pdfIn PDF document text
    • http://lorichphoto.com/pictures/file/toxofojewavoluwaxorexi.pdfIn PDF document text
    • http://kaies.net/upfiles/file/90498899792.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/gabir.pdfIn PDF document text
    • http://veterina-hrib.cz/user-uploads/files/kibipasibeziw.pdfIn PDF document text
    • http://hotspot-usa.com/js/upload/files/judupexejogeluki.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/hjgsiqfjjmb46bo8maptndvmd6/26500837110.pdfIn PDF document text
    • https://renault-service.com/userfiles/napuwi.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/62ohk733riu8gkqd8ljeagq7p1/99384003877.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/fovofobosilup.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4b8e024e0---97964515051.pdfIn PDF document text
    • http://195exim.com/datas/files/75680905404.pdfIn PDF document text
    • https://tanasiri.com/piceditor/file/vafevenimoxexupowavo.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1611a72f811bf7---96008630754.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/92077137082.pdfIn PDF document text
    • http://maquinandoysubastando.com/dleyes/admin/fotos/file/87555186431.pdfIn PDF document text
    • https://rotitelor.com/contents//files/xasapojopuledoxa.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_off0000bddc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDDC 16676 bytes
SHA-256: fba05a963d3d112d02c522ec7e77a0b17b1394f074dfb50a2de359eac82cedda
font_01_sfnt_off0000e97b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE97B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10192 10684 bytes
SHA-256: a689c6b2a35cf9265d64b0dbce35e12fbbbf1778e5d61f54789f14d047914945