Malicious PDF — malware analysis report

Static analysis result for SHA-256 39043abc63a94e59…

MALICIOUS

PDF

75.2 KB Created: 2021-09-16 21:53:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: ab567d1c1da2ee057fb07e47a8993e6a SHA-1: c0613ee67d2f7203d9ceac0e110ce75a81084a04 SHA-256: 39043abc63a94e596f0736914fb7c64f5620df3a97cbab239b867320e6396bb7
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, indicating a phishing or trojan payload. The presence of numerous embedded links to external PDF files, coupled with a heuristic indicating a 'download button' lure, suggests a phishing attempt designed to trick users into downloading further malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the malicious intent by highlighting the use of disposable hosting for multiple links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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://netshopnepal.com/userfiles/file/dewegagibipobale.pdf In PDF document text
    • http://vejwun.cz/images/wikemodete.pdfIn PDF document text
    • http://iburgisidimarsala.eu/userfiles/files/30632033539.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/borudazozinasafifanoku.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/161407b57090f3---keterovojoned.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/roxasolijewozu.pdfIn PDF document text
    • https://jackyrouxmethode.com/userfiles/file/nebakusaromakirimulanuvuw.pdfIn PDF document text
    • http://delve-cr.com/uploads/53628343512.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161415a05881f0---68447960866.pdfIn PDF document text
    • http://ever-pioneer.com/upload/files/nujugexelosojir.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/ribakuloxop.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/finabaxagemev.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/35334954031.pdfIn PDF document text
    • https://bomnuocebara.com/quangbasanpham/app/webroot/upload/image/files/82073855329.pdfIn PDF document text
    • http://miyagi.chi-kara.net/Upload/files/zepuwa.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/45299695384.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/21312629022.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/7368192690.pdfIn PDF document text
    • http://ropesadventure.com/d/files/mefojifelojerokota.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/9106066219.pdfIn PDF document text
    • https://kmkmekanik.com/upload/ckfinder/files/vokam.pdfIn PDF document text
    • http://186086.com/upload/files/66610251938.pdfIn PDF document text
    • http://lapempi.nl/ckfinder/userfiles/files/84326763254.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=update+idm+to+latest+versionPDF 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_off0000c1b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CD 10628 bytes
SHA-256: 6bcfbb87d7939d51816f7a40f4a93f0ddbe70c9629e5b5800777659eea772bc5
font_02_sfnt_off0000f21b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21B 17396 bytes
SHA-256: 7838c579a6b1c907e015eaa92645dd71a2f12642aec3fc63a331082fdd9fc3f9