Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a3795f851785363…

MALICIOUS

PDF

97.0 KB Created: 2021-07-14 03:52:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a7f6a3d5909bf1c2cd88da95b98fa48c SHA-1: 529ea1cf4c757ae0b2596c49e0e24ef8c7d95294 SHA-256: 5a3795f851785363f0da4ab3b0189a0cbf4a4b4d9501db5b0cf97a793343204d
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites and act as a link farm. The primary purpose appears to be directing users to potentially malicious external sites, leveraging compromised infrastructure for hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/61tr39kh0e09vep66rs6nv7s64/63007301848.pdf In PDF document text
    • http://rlangkhan.com/upload/userfiles/files/jimivapukejazurat.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160813575207e0---83347330712.pdfIn PDF document text
    • http://myphamasia.net/upload/files/7764981721.pdfIn PDF document text
    • https://mayphotocopydogia.com/upload/files/nijuzugutowol.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/m9hmjanrefva6o0lnmkhpckn69/81303734559.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0e14370196---tomizupilajinom.pdfIn PDF document text
    • http://lhsclassof1971.com/clients/74120/File/giborifosozafu.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/47392a82e9e4d7b17798a5adf6e3e1d7/11195937581.pdfIn PDF document text
    • http://ibb-online.ru/f/file/kobulidipugavudijivome.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093a8a744372---23296720753.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/ximenunijewuja.pdfIn PDF document text
    • https://jamurgoreng.net/contents//files/23658546438.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/kuguko.pdfIn PDF document text
    • http://hopkinshigh62.com/clients/7/77/7764523e397120ad9b09b1da26998858/File/melopetofexebinujigaxo.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/4cf359e0cda6a6625dabd40a4d31568b/lajaxejeg.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/spblfe0h5upv0cuspjmtn5aq2t/49336643687.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/e2136a491a5b2e09b0fd28c62c59b877/14594455375.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/38017012550.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160717e6d32cdd---tazafepapijunef.pdfIn PDF document text
    • https://yz-yongzhong.com/upfiles/editor/files/46146752292.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/tndrtl6ique09bs8rpfdkbqko2/lenozabafubeduluzat.pdfIn PDF document text
    • http://canadanur.com/resimler/files/seruxexowotumemegidolad.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16096fb6271064---66209842316.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=philly+cheesesteak+egg+rolls+dipping+saucePDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001170c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1170C 11100 bytes
SHA-256: f3ca7753558d282bc4c5b5448a29ce1b0f364b54e022ed8262dc5ef8b9ea3e31
font_02_sfnt_off000130bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130BC 18024 bytes
SHA-256: 3af892b8942a48dd7a8a343fe52dc40523a044e0e158e22432b7ba321ba6a219
font_03_sfnt_off00016024.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16024 16312 bytes
SHA-256: 7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae