Malicious PDF — malware analysis report

Static analysis result for SHA-256 2fa90fdfbf034542…

MALICIOUS

PDF

71.5 KB Created: 2021-09-24 17:46:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 850c1991cc5a6d77206d746d6c94a50a SHA-1: c4c6e042b76f142710a0b8823006112ecdaafbe5 SHA-256: 2fa90fdfbf034542e6257f3b2c62718691586f711a0149ad5d287f7b0d5ad8fb
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with one rule specifically identifying it as a 'PDF link farm points to compromised-WordPress upload storage'. The ML classifier and ClamAV also strongly indicated maliciousness. The embedded URLs, while some are marked benign, are part of a larger pattern designed to direct users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://ibliberia.com/ckfinder/userfiles/files/70315765928.pdf In PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/vifidojanekapudolik.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e2d2521ad---dubisutaram.pdfIn PDF document text
    • http://carrozzeriabosini.net/userfiles/files/mojofutudatuzino.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/nexevevabozesosilulukif.pdfIn PDF document text
    • http://bretagne.annuaire-regional.com/ckfinder/userfiles/files/kututopopififusi.pdfIn PDF document text
    • http://frickcontrols.com/uploads/files/47038861948.pdfIn PDF document text
    • https://drivetripper.com/userfiles2020/files/sebubajela.pdfIn PDF document text
    • http://isystem.hu/userfiles/file/gidedojowufo.pdfIn PDF document text
    • http://lonniestireandauto.com/nbloom/fckuploads/file/19297375189.pdfIn PDF document text
    • https://huaku3c.tw/uploads/files/202109101923083826.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/24584711433.pdfIn PDF document text
    • http://sxnqx.org/upload/file/Fl202109020118073190.pdfIn PDF document text
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/zusamubetafonavosulimep.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/e1fb8492bbfaef5cd46a557d9b2d56e6/xoletip.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/pavebadir.pdfIn PDF document text
    • http://dgxzz.com/uploadfile/file/zimaxafotanexud.pdfIn PDF document text
    • https://upaspor.com/resimler/files/67366492600.pdfIn PDF document text
    • http://jingkangchem.com/upload/files/55255430513.pdfIn PDF document text
    • https://angelsolutions.ro/ckeditor/ckfinder/userfiles/files/2939875861.pdfIn PDF document text
    • http://uni-soar.com/userfiles/file/zalebitago.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/vbu56dub390imon6f7vsfokmif/65010402825.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/94613747121.pdfIn PDF document text
    • http://freetds.net/userfiles/file/xabagorewijozirani.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=green+screen+video+apk+downloadPDF 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_off0000b4c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4C1 16800 bytes
SHA-256: 306901f1f69659f00d44441f12ec9e52a0f02e873e6f25196c8f49679f18711b
font_01_sfnt_off0000df46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF46 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f75d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75D 10692 bytes
SHA-256: 0aea5d7bc695da8a90c31d4cdacbba7eee217828e1f3067a0c73c34f6f51a95e