Malicious PDF — malware analysis report

Static analysis result for SHA-256 d85538a39d8f4cb8…

MALICIOUS

PDF

107.2 KB Created: 2021-09-08 05:05:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5ae73eefef438e499f10873901dbe3f0 SHA-1: 874dc5d2a2dfc8d63f096719a192171f305bf2a2 SHA-256: d85538a39d8f4cb8a90a8819973976b691d942c885e4aabb5922c8d323ed4c9f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly indicate a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://smidgel.ru/uplcv?utm_term=adobe+pdf+editor+license+price PDF link annotation
    • https://alakharia.com/public_html/userfiles/file/wobuxifejoluzenanubitinuv.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/d47fuav67vllupbosl5b36p8hn/72916317116.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/5oivb3jhk7hsjavvggudnb32te/77953143894.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/84671961882.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083ad3187bec---41953015764.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/sogelasaximopemumalokilej.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/gobasowibugezev.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a91d66888fe---38990446291.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/1eab2af1a7f04efdaf66ab19f3f16f3c/36474335715.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f4826d658e6---13629350814.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/zesopav.pdfIn PDF document text
    • http://netisiletisim.com/guvennet/resimlerfiles/gemilurapigevopokat.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/fegizamojenekiletagoxepuz.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/zelegixipibuwutig.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/suwowasimasinixe.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aea5eda2663---vanubukikeg.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/00694dd092e5b71e92c06b714d45a7e0/34410114676.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160869f6fa4756---gemow.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/98751842514.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/88279421552.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c061753da1---fonirozalotexifowuvozi.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/lifexojifanutiv.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/161217b8ace50d---tuxut.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/nudawup.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/65041458127.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_off00013c5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C5B 19284 bytes
SHA-256: 728d6ec4636e52e48f1c460f4053d4040ca95f7a7fc5a9252e724d7a23185b46
font_01_sfnt_off00016ea2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16EA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000186b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x186B9 10572 bytes
SHA-256: 083eb2a4244fd917c17f12a49bbbaedf45ebe434436c3c06484b9cd4b33d854f