Malicious PDF — malware analysis report

Static analysis result for SHA-256 84cc711c97c1db42…

MALICIOUS

PDF

81.5 KB Created: 2021-09-22 23:22:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 918081c301952cf5188af358f3bbfd5d SHA-1: 86574faec29cb11141a874fa61ed3e9deb4745b1 SHA-256: 84cc711c97c1db4229d3fdd4335f83073e83034ca6535e9235b6d47fbc4d2eb2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The presence of embedded JavaScript and numerous external URIs, many pointing to compromised CMS uploads or disposable hosting, indicates an attempt to redirect users to malicious sites. The primary function appears to be acting as a link farm to distribute further malicious content or facilitate phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 7

  • 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.
  • 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://laborke.ru/uplcv?utm_term=oreo+tv+free+download+for+android PDF link annotation
    • http://seychelles-resort.com/images/blog/file/90370684746.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/mawiwebexezokizimin.pdfIn PDF document text
    • https://www.studiorosaliabusco.it/ckfinder/userfiles/files/54004047409.pdfIn PDF document text
    • http://www.erealitysolutions.com/tennisontario/assets/appsadmin/js/ckfinder/userfiles/files/74037060898.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202109112258394766.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/1615661401.pdfIn PDF document text
    • http://yilbasipromosyonu.com/userfiles/file/83603884810.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f56c08006c---98640880216.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/e8800d616cc4dc06692e2569223a0e95/wisisi.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/68076294533.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/viieasc3slgvl8dq837dv48ua6/3767200680.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/zoliduvuwigi.pdfIn PDF document text
    • http://eatoceanic.iorderfoods.com/uploads/files/15650988260.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/gedevemeluzanatazewinu.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/tabigivozotukidoxukawoku.pdfIn PDF document text
    • http://maytinhnangdong.com/files/uploads/editor/files/76588730352.pdfIn PDF document text
    • http://cl-pub.com/files/files/noxipesuruvem.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/83733983203.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/aktt12sr5ha6icf4oougsp0drq/risovozoki.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/99538895576.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/jidagadulesakep.pdfIn PDF document text
    • http://rzn-house.ru/upload/file/jatel.pdfIn PDF document text
    • https://togeltop.com/contents/files/molorapurabubexiva.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/4606538768.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_off0000dcb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB5 16932 bytes
SHA-256: 0e4d9579f9aa1837a02cd8aa33b9001fd1e2057fe192ee9dae0a01612a3b6460
font_01_sfnt_off000108a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A4 10356 bytes
SHA-256: dea710ce6f01d4d6bd4710c1e89780a35b304c9254735db9129e38eca0bf9d1d
font_02_sfnt_off00012034.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12034 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1