Malicious PDF — malware analysis report

Static analysis result for SHA-256 157ef04c8e76c701…

MALICIOUS

PDF

87.1 KB Created: 2021-06-28 05:01:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: ef6e299dc594bc89cc091b69e8a3c344 SHA-1: b2c0eb52694cab2675bc70d0391df671e735f4d4 SHA-256: 157ef04c8e76c7010b66713f5cf008bc9a06ced7ac3d4836f989790506665de6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites, suggesting a link farm designed to redirect users to potentially harmful content. The presence of these links and the nature of the hosting indicate a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/stavv43rkkfa468v2safu73olt/91484341000.pdf In PDF document text
    • http://yngc.ru/admin/ckfinder/userfiles/files/57307953471.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/f53a1fe17db7be8d8bcc113790ab8c1c/rotekojivemiwavakuxudeke.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160768250e5b7b---47975741532.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/13e9bc8263da8a2b0da9b6b58284508c/zolosadefobigipolosu.pdfIn PDF document text
    • http://retroldn.com/userfiles/file/wogukizewowegisiw.pdfIn PDF document text
    • https://graveyards-fuj.ae/userfiles/files/fotixiguvo.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/vt5ps0g6lp90ktqf3a61v28jif/85910999154.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb30ee31603---renezojaluberevo.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/91b13c1d2517f5098e8d833dba79583d/nurilokulexibis.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/ct25pjddmroc00314qhqbr7tfu/54537170657.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/xonadogep.pdfIn PDF document text
    • https://majubesar.info/contents//files/55703292921.pdfIn PDF document text
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/59296958021.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/pazakasesonovuguverun.pdfIn PDF document text
    • http://volamtuyetthe.com/userfiles/file/14629583981.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/7038c2b139b37c6df83885030a96b85c/pukozofamitafepefipujonit.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/iu9vpeanmaumm4b9fqf9jt6gh0/lesigodurasur.pdfIn PDF document text
    • https://bleikss.com/userfiles/file/56310718393.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/72d337c2dbc69f594545886edd797387/gelumomufibitupotewexipo.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f71a174a66---36917892376.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/4ae068c5f7de3593bebb1fb76422740d/21707180763.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/68352628684.pdfIn PDF document text
    • http://asianmosaicnyc.com/userfiles/file/sodonoranawovirajisomex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=as+soon+as+possible+short+formPDF link annotation
    • 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_off0000ec0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0F 10744 bytes
SHA-256: 37bef9559bed29b74d693a5b2eea99700c2013dcc0408840c4a4bb7775d69e90
font_01_sfnt_off00010451.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10451 20688 bytes
SHA-256: ef4a35ea3e4d0d969a547e6fd5045f697d4b511256902deb7cbacd82a56fcbb9
font_02_sfnt_off00013804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13804 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1