Malicious PDF — malware analysis report

Static analysis result for SHA-256 57edb9b6a16d6c05…

MALICIOUS

PDF

71.7 KB Created: 2021-09-26 08:52:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2b331ddbaa615c5f13133b543fa5a8c7 SHA-1: dac299bf6a66f465f1426083b55bd4334115f111 SHA-256: 57edb9b6a16d6c058970e03d3cfba4e640e7e5fb14496d0992467302a1a938e8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161324811c8876---19834116642.pdf In PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/62098773823.pdfIn PDF document text
    • https://jxlmedu.com/file/files/20210923_070313.pdfIn PDF document text
    • http://csc0512.com/userfiles/file/20210910054226_xey6zj.pdfIn PDF document text
    • https://bonvoyageindia.in/ckfinder/userfiles/files/masenekurujafadubi.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109180046539677.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/buxar.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/27320989727.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/161330d9f9502a---94200377913.pdfIn PDF document text
    • https://tunguoilon.tunhua.vn/ipp/images/uploads/files/pavuzodegimulaloz.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/38eb5b39ec63a4cc245047d1bdeeb940/45387637399.pdfIn PDF document text
    • http://centralcogtc.com/uploads/file/17641868459.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/75218313445.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16147ea1f01580---68020754285.pdfIn PDF document text
    • http://letsfinal.com/userfiles/file/wulibuganeguduxodobolubu.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/057cee5a40ba097449ae7ee09ea9fcb9/27182135029.pdfIn PDF document text
    • http://canxetaianhduc.com/images/file/kujewagiduvutugolidurot.pdfIn PDF document text
    • https://jesssmithtri.com/jesssmith/ckfinder/userfiles/files/60790478041.pdfIn PDF document text
    • http://519pf.com/userfiles/files/bevupaxunutegagizofi.pdfIn PDF document text
    • http://qdsenfeng.com/data/files/44984231222.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/gm2op3dravk6pplrcru2bmlnbi/78498000313.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/gufuxitofijufasumuk.pdfIn PDF document text
    • https://khanoomhoteli.com/basefile/khanoomhotelicom/files/62367615172.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/bojixekugexadunipu.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/30887937727.pdfIn PDF document text
    • https://mashura.co/userfiles/files/77168996351.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=invasion+of+the+body+slammers+tom+and+jerryPDF 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_off0000b43c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB43C 17012 bytes
SHA-256: 9ca29384f0fb980ffacdd58b59626d46887af7b5fcec6085a3ae75caf0a2c636
font_01_sfnt_off0000df5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF774 11020 bytes
SHA-256: 5c9591efb6b4490495c580a26d34800f6894cf886ebb62b5cff9af17b6ecff88