Malicious PDF — malware analysis report

Static analysis result for SHA-256 b86628684698b453…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 14:32:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5d5ea9a99c3dbb24088421807acb7326 SHA-1: 7025e2a02652a607a92faa210775b97063da24b6 SHA-256: b86628684698b45399fc70771f260851e7a80b1b80d85561b31fca7cc3c7d072
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. The embedded URLs and the PDF's structure suggest an attempt to redirect users to potentially malicious sites, aligning with phishing or malware distribution tactics. No scripts were extracted, but the PDF's nature points to exploitation for client execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://landi-bg.com/images/file/86739337432.pdf In PDF document text
    • http://downtowncincyhotels.com/core_degree/admin/images/cms_imagesfiles/42559046087.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/44860059499.pdfIn PDF document text
    • http://vaonhaphatphap.com/images/uploads/files/nazowilu.pdfIn PDF document text
    • https://tucarrorentacar.co/ckfinder/userfiles/files/55152987456.pdfIn PDF document text
    • https://mjrspot.com/fckimages/file/pomalifirojege.pdfIn PDF document text
    • https://lecachet.fr/docs/files/61274521182.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161451f0ae30fd---93727495429.pdfIn PDF document text
    • http://nabisori.com/userfiles/file/lejexasujazivutawomaku.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/45796607553.pdfIn PDF document text
    • https://ihappywash.com/uploads/files/202109081124197813.pdfIn PDF document text
    • https://rt-totaalafbouw.nl/userfiles/file/14041809897.pdfIn PDF document text
    • http://tryinvest.eu/userfiles/files/68800700905.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/zepotolorufisupe.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/18666886573.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/qjt1b993796nppee4rue6ufo2c/47878673469.pdfIn PDF document text
    • http://sichera.eu/userfiles/files/71631924504.pdfIn PDF document text
    • http://paglialonga.it/userfiles/files/77065063029.pdfIn PDF document text
    • http://belovosushi.ru/files/sabasuletej.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210906_8FD8593AD0743A55.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/bunukejefune.pdfIn PDF document text
    • https://defi128.com/userfiles/files/30631384226.pdfIn PDF document text
    • https://valergences.fr/userfiles/file/56690761280.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/84152023282.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/57059479991.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=back+button+anywhere+apkPDF 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_off0000d906.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD906 18820 bytes
SHA-256: 4b52fbf9ce81854463f6aa9b2e5fe121f1cd06cd61e81808cc66ccab40b0fbff
font_01_sfnt_off000109b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121CC 10748 bytes
SHA-256: dbdc13085c06a01bc1ac40875341e1ee10b27cee528336e6142fb484be943cc0