Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a66f94a740fd7b1…

MALICIOUS

PDF

79.3 KB Created: 2021-09-14 08:26:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b19e1e7f11efefdd22d693a0b668829e SHA-1: afac6e430a43fabf73ea271dc51f6067be5faa3f SHA-256: 8a66f94a740fd7b1ea2379505be3d38ad5a7640a19a116c324bac8f3609786cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites and disposable hosting. The primary purpose appears to be redirecting users to malicious content, likely for phishing or malware delivery, as indicated by the 'link farm' and 'compromised CMS upload link' heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://medvor.ru/uplcv?utm_term=android+slide+to+unlock
    • http://tokstar.com/_UploadFile/Images/file/zibujulofileseteros.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea330004d4---dugijikakaxaji.pdf
    • https://lifesmart.ro/ckfinder/userfiles/files/tisofom.pdf
    • http://pospatrans.cz/UserFiles/File/rotorevat.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161364ff696e2e---32605576081.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613815c2ed4a0---nudomutekakuxaxoxos.pdf
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/15678934747.pdf
    • http://mebel-moscow.com/content/xuploadimages/file/zixiduguvalede.pdf
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/zitusumutiwalovip.pdf
    • https://karolinanowak.com/userfiles/file/kuzeginu.pdf
    • http://miraesusan.com/ckupload/files/52625542545.pdf
    • https://garraldaarquitectura.com/garralda_userfiles/files/35652030657.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613f8455367c9---rubagimenimizo.pdf
    • http://a2hgghk.handylover.com/upload/files/jedafozimidi.pdf
    • http://www.brickchamber.com/ckfinder/userfiles/files/dazej.pdf
    • http://rigdrilling.org/userfiles/file/makikatidalikozawikome.pdf
    • https://shriramsteels.in/public/ckfinder/userfiles/files/mefetobosapokifotawok.pdf
    • https://franchiseharbor.com/files/files/fapovutawiwegalazivi.pdf
    • https://pasarangroup1.com/contents/files/44197220641.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3700c0ce7---38689050684.pdf
    • http://ptichile.cl/userfiles/file/kipiwizojavixulaxoporunu.pdf
    • http://geoplan.su/userfiles/file/66016043977.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d1fb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1FB 16792 bytes
font_01_sfnt_off0000ea0d.bin
65f6d60758f5c91fe7eef90719d0d3b0493a898429a308ac52b22dd7b6cdea73
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0D 17828 bytes
font_02_sfnt_off0001183c.bin
9c92dc05b477382eeeb07e188d9bccc99fd8c6025704a9dea335e0ff0bb97e72
pdf-font-stream PDF embedded font (sfnt) at offset 0x1183C 10372 bytes