Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5925fd32064967d…

MALICIOUS

PDF

98.2 KB Created: 2021-09-19 11:01:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3491468696f16978f9299fe91f83831e SHA-1: e2e53b84067cde9c2413c2f51d69df09c744f1c5 SHA-256: b5925fd32064967de3dedda0b94d5d61ec0822174ed217b2345084a7a86a922e
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, presenting numerous links to external resources, one of which is a disposable hosting domain. While no scripts were extracted, the presence of embedded URLs and the overall structure suggest an attempt to redirect users to malicious content, likely for downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://sankaibearing.com/userfiles/files/86040941139.pdf In PDF document text
    • https://halead.com/uploadfile/1631944616.pdfIn PDF document text
    • https://www.mtiwelding.co.uk/admin/ckfinder/userfiles/files/bijusunaselakuvaxutuxi.pdfIn PDF document text
    • http://teranor.com/ckfinder/userfiles/files/86774848381.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16133678d7b423---40651105484.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/mibepirijurusubivumorel.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161409e25685a4---lijadavijagudifef.pdfIn PDF document text
    • http://targhevaticane.it/userfiles/files/40577368463.pdfIn PDF document text
    • https://birudongker.com/contents/files/44717414410.pdfIn PDF document text
    • http://airfa.it/userfiles/file/15973324002.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/92514518477.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/31750573201.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/99067966101.pdfIn PDF document text
    • http://yokohama-model.com/userfiles/files/koril.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/dexikotizusewa.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/20686252392.pdfIn PDF document text
    • https://bnovum.hu/downloads/32908052497.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/kibobiwul.pdfIn PDF document text
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/tawufowa.pdfIn PDF document text
    • http://ctmmaximoravenna.com/ckfinder/userfiles/files/xigerizovawavig.pdfIn PDF document text
    • http://guidesdugrandlarge.fr/images/import/file/xodufixexiruxowoditunu.pdfIn PDF document text
    • http://way-of-spirit.ru/upload/file/57735215277.pdfIn PDF document text
    • https://lecachet.fr/docs/files/39035850689.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/rigakoxatixesalefirudak.pdfIn PDF document text
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/53945042918.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=dragon+ball+gt+androidPDF 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_off00011a31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A31 10264 bytes
SHA-256: e4b19c670d70d7c084c37749dcef3bff2ad272be9ca5528b25bc95025af6abd6
font_01_sfnt_off00013114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13114 18776 bytes
SHA-256: 37482982ef9cd6d1884a1584c9d123cc02b701e6c0fd8bc5d9e6d46985183165
font_02_sfnt_off000162ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x162EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1