Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4c5dca82e1ab2c6…

MALICIOUS

PDF

86.4 KB Created: 2021-09-17 07:46:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 72518cf1d6c9222e40ea6b9e084944d2 SHA-1: 727a0dbaf71186d3b9e1fcbda70fc4388d8eda5d SHA-256: d4c5dca82e1ab2c6bae0d16df18857091b12b33cd8e15327ce65edb6286f0487
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier also indicated maliciousness. Numerous embedded URLs point to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The file's origin from wkhtmltopdf suggests it was likely generated programmatically for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://pixomot.ru/uplcv?utm_term=que+emulador+de+android+para+pc+es+mejor
    • http://servicedental.it/userfiles/files/lugofotikebu.pdf
    • http://orderbestwings.com/uploads/files/83526427476.pdf
    • http://lifeisartfoundation.org/sites/default/files/images/userfiles/file/lidajekikaxinepepukomoga.pdf
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142044ddf31f---guwifudejovijuna.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/3l8ktlitc5rnr8eptltpkadg14/kilupokabidiro.pdf
    • http://atrsara.ir/resource/files/lafijasujiwiludojumezew.pdf
    • http://greenhousehotel.vn/uploads/image/files/33907689578.pdf
    • http://ktcz.eu/files/files/23343191539.pdf
    • http://websurin.net/UserFiles/File/gapaxunakamaluxuv.pdf
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/jovebudekafega.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e7720fbc7---zedafugo.pdf
    • https://aluminiosarla.com/userfiles_arla/files/dodobukekirukilejazivupu.pdf
    • http://labuchedeberce.fr/userfiles/file/paxokivelutijipeka.pdf
    • http://geometrarontani.it/userfiles/files/devumew.pdf
    • https://ofertaromania.ro/ckfinder/userfiles/files/98205836256.pdf
    • http://crosswaysrecruitment.com/userfiles/file/1919036027.pdf
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/cl4lk835etgr0qsfmgcrq1tlno/befafekep.pdf
    • http://reflita.lt/uploads/files/mizavikig.pdf
    • http://schokoladenfontaene.de/idata/77929589602.pdf
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec1fd040ff---zasixogalukovepomixen.pdf
    • http://www.naturhalles.fr/fckeditor/userfiles/file/38301962780.pdf
    • http://bioident.pl/photos_fck/file/merabose.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/161409f8c4c1fe---66340402926.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_off0000e9cb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CB 16792 bytes
font_01_sfnt_off000101e2.bin
dfc30ae98a752114541f7d5c1e72018049f02bf6d7e053af3eca1c263ec7938e
pdf-font-stream PDF embedded font (sfnt) at offset 0x101E2 10864 bytes
font_02_sfnt_off00011ae3.bin
19e0a74488f1eba5fa8a1056d41172cef7ca3134cdeaa98e2f09313d91d69de9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE3 18632 bytes