Malicious PDF — malware analysis report

Static analysis result for SHA-256 2bd76d3c2f283533…

MALICIOUS

PDF

88.3 KB Created: 2021-09-11 12:37:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b58b51de594fdc0897ff64750630beca SHA-1: 41bd342d07b599010b8d2ec5b8578d48473ab717 SHA-256: 2bd76d3c2f283533ae5cf0577761e1bd429eca451821a6ef1ecc23c37a7b5c9f
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. It contains multiple heuristics indicating it's a link farm pointing to compromised websites, specifically WordPress upload storage. The embedded URLs suggest a phishing or malware distribution attempt by directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/e6bc9771304bff98113a9f8707247873/kumax.pdf In PDF document text
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210901_095514.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/15269857132.pdfIn PDF document text
    • http://uralcomservis.ru/crn_fls/crn_files/gazutibuladipu.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/67526334632.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/6236550180.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/6c877489e5caa724a360bfe9fa369dae/76942810368.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/wariwosujavepaji.pdfIn PDF document text
    • https://cvssteelex.com/ckfinder/userfiles/files/21477754798.pdfIn PDF document text
    • http://tprcindia.com/ckeditor/ckfinder/userfiles/files/dowodaxavamosisat.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/96970589441.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/midafopol.pdfIn PDF document text
    • http://9meclinic.com/ckfinder/userfiles/files/notivinomurubujokep.pdfIn PDF document text
    • https://stancijanegrin.com/userfiles/file/jizejaxigerajakiririgo.pdfIn PDF document text
    • https://maffart-guy.com/userfiles/file/53940583354.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/50579756982.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/82774998735.pdfIn PDF document text
    • http://canphantich.net/Images_upload/files/73420087860.pdfIn PDF document text
    • http://kbchina.de/upload/bakomalorewev.pdfIn PDF document text
    • http://24cvety.ru/upload/files/fajepeduvo.pdfIn PDF document text
    • http://kepco-group.com/uploaded_files/userfiles/files/xikumetariruwomuri.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/161390811f050a---zaxepuminizolev.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/rakeboxizitog.pdfIn PDF document text
    • http://nitecoreromania.ro/files/file/mofenugigodixowiget.pdfIn PDF document text
    • http://www.pro9apps.com/app/webroot/files/uploadimagesfile/roguturepowexepijaviluziz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=grammar+workbook+pdfPDF 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_off0000f605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF605 18012 bytes
SHA-256: 06ac359c80c6dbf989a48891b5af64b0e7ca8c8038d7e07b646c81a57033b87f
font_01_sfnt_off00012493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12493 10376 bytes
SHA-256: bcc7c25da4fbe0f5426727fc6c6f70469f6d2ae2a7d96334884013be2315b074
font_02_sfnt_off00013be0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1