Malicious PDF — malware analysis report

Static analysis result for SHA-256 b861828cb785299c…

MALICIOUS

PDF

82.9 KB Created: 2021-09-18 17:49:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 84def3b8a8664820e62f081aedd96bc1 SHA-1: 443191d1e094a9e592e44f80781720649871fa23 SHA-256: b861828cb785299c73b23a4d2ec1124a305f3252caa167a9df8c1792251aad6a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable hosting, suggests a link farm designed to redirect users to potentially malicious content or phishing sites. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://synerhu.ru/uplcv?utm_term=world+cricket+championship+hack+version PDF link annotation
    • http://ttmplus.com/userfiles/files/15854543828.pdfIn PDF document text
    • http://veterky.ru/ckfinder/userfiles/files/16218105899.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16142d9cd2a42d---14941549268.pdfIn PDF document text
    • http://qhchemicalsfeed.com/upload/files/jiluxumogokalobelejuzu.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/gumut.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/26636794886.pdfIn PDF document text
    • http://dailitara.lt/bites/uploads/file/8214958588.pdfIn PDF document text
    • https://ka-base.no/images_content/file/67538830525.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/bubunujetokir.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/20324889502.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613a02300538f---didonesidudelaxuwanurag.pdfIn PDF document text
    • https://em.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/ranupiwugufujisimuvad.pdfIn PDF document text
    • http://esrafisek.com/images_upload/files/fevimigidusawijixelefek.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/fezutov.pdfIn PDF document text
    • http://golfvillageonline.com/userfiles/file/70503956492.pdfIn PDF document text
    • http://elektromig.pl/userfiles/file/zuguzusasurelora.pdfIn PDF document text
    • https://helices-evra.com/userfiles/file/zezup.pdfIn PDF document text
    • http://unionnutritech.com/upload/files/rabopatogelekoragil.pdfIn PDF document text
    • http://gamjagolla.com/uploads/files/13920702905.pdfIn PDF document text
    • http://istocdukkan.com/userfiles/files/18653297143.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/36151570568.pdfIn PDF document text
    • http://tradotel-riviera.com/file/60998174708.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/3166104870.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210912135431.pdfIn PDF document text
    • https://megacook.pt/site/upload/file/lukerasolafofufuva.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_off0000de75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE75 10928 bytes
SHA-256: 8e19eb86ec5a29a4e2c49c6da9f03a08ee278cfdbe384e69598a0b18686464ac
font_01_sfnt_off0000f797.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF797 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA9 17604 bytes
SHA-256: 8744a4c893e7965163d623b3a44b160d0a4087b953c16d38e383fc18eb3a987b