Malicious PDF — malware analysis report

Static analysis result for SHA-256 6446bb30a6511112…

MALICIOUS

PDF

78.5 KB Created: 2021-09-28 21:59:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8df7253ecc88bd5e9aaa5723ef39c829 SHA-1: cd61ac615a4d9513174ea7429ccfe8b4f5f45e99 SHA-256: 6446bb30a6511112c2db7f1fe5d67954854bf16b19f137a8e52c2ace933a167c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious content. The PDF contains numerous embedded URLs that point to external websites, suggesting it functions as a link farm or redirection mechanism. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest the document's purpose is to direct users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://medvor.ru/uplcv?utm_term=heavy+games+for+android PDF link annotation
    • http://pincesorvarshop.hu/editor_up/18329131395.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/rezabolugidakozos.pdfIn PDF document text
    • https://cemb.ca/upload/editor/file/mowogusokasawizidigixiz.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/33618461550.pdfIn PDF document text
    • http://mauthietkedep.info/upload/files/85375128102.pdfIn PDF document text
    • https://tahubunting1.com/contents/files/ritadevumemutodexanupabok.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/duwotubekaxigosa.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/39097010564.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/bekajoronetiron.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/51525226857.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/giwanusewixova.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3a6747419---99855450415.pdfIn PDF document text
    • https://luxurybaths.marblobaths.ph/app/webroot/img/files/78331533695.pdfIn PDF document text
    • https://coffotea.com/uploads/files/202109170702308460.pdfIn PDF document text
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/jukipafoxibo.pdfIn PDF document text
    • http://drsrkbedcollege.com/ckeditor/ckfinder/userfiles/files/fetebirovamomikokunopeki.pdfIn PDF document text
    • https://www.antoniopopolizio.it/ckfinder/userfiles/files/7634494698.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614e77d22aa4d---30016664139.pdfIn PDF document text
    • https://makanbanyak.net/contents/files/26859394741.pdfIn PDF document text
    • http://cathugo-yachts.de/res/wysiwyg/file/69728641743.pdfIn PDF document text
    • http://delve-cr.com/uploads/dazew.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/nesifekapekagiwerim.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/83967104610.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/tofuvurodetafi.pdfIn PDF document text
    • 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_off0000b7f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d00a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD00A 16232 bytes
SHA-256: 01cd0e4798e93fb086042d610f43ddeed7bf091af48aa863f5c4a4f61b651684
font_02_sfnt_off0000e5df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5DF 17812 bytes
SHA-256: 66fdb44508c082c6623a713d2290af69f63bc08419b348fc365a886cbf22beaa
font_03_sfnt_off0001138e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1138E 10724 bytes
SHA-256: 8e38028db7e4303a30dad9c5f5cd85b19fcf00d82bb3142ef2251fe219724ec0