Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ff4ed937eebabc6…

MALICIOUS

PDF

72.6 KB Created: 2021-09-28 15:17:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2d3d00542f4099b98b1637e3b57a4b11 SHA-1: 2cdb9d563c5fc0b82c7cc85116ee43d682f10a12 SHA-256: 7ff4ed937eebabc6076d79aca0931a4ab9e78bb13b77cf5a84b921e25f1edde5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to numerous PDF files. One of the embedded URIs, disguised as a movie download link, is a strong indicator of a phishing or malware distribution attempt. No scripts were extracted, but the PDF structure and numerous external links suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://favourtec.com/attachment/file/34747145885.pdf In PDF document text
    • https://siltri.com/fck_upload/file/28806998078.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/vosaxagisobaruvanagubine.pdfIn PDF document text
    • http://goksirkrupskimlyn.pl/img/upload/files/pozijamamewoperiror.pdfIn PDF document text
    • https://icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/86835368695.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1631051764.pdfIn PDF document text
    • http://orderbestwings.com/uploads/files/pokaginuwa.pdfIn PDF document text
    • http://feldbach-tourismus.at/files/vubasemesexasikuto.pdfIn PDF document text
    • http://uhorder.com/upload/files/fodujajowi.pdfIn PDF document text
    • http://sunpix.ru/img/lib/file/nefuxek.pdfIn PDF document text
    • https://cancelaria.pl/galeria/file/novalenusonelipovaweg.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b366dd0dec41d7173eeac7abce1e8fc8/69304470017.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/50665118070.pdfIn PDF document text
    • http://cuacuongiare.vn/upload/files/80526621471.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/72109091768.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/56225625793.pdfIn PDF document text
    • http://hsaltsj.com/uploads/files/41367791801.pdfIn PDF document text
    • https://zaragozadenoche.es/upload/files/nuniwubawodifezenuvepowel.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/sukudegikoper.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16139e95a679c2---29641998049.pdfIn PDF document text
    • https://pt-lb1.pasarantogel.com/contents/files/10939974047.pdfIn PDF document text
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/megowetabidigesexo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=zack+snyder%27s+justice+league+download+4kPDF 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_off0000b1aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1AA 18584 bytes
SHA-256: 237f43b1e22d4ac115204130cae35c2078e6efc951c1c9be705ca551df0be2c4
font_01_sfnt_off0000e248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE248 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA5F 11144 bytes
SHA-256: dadac2d6c155ca036946b6e057d108d4f165ecb3c77e48d9c056a6057bd8b83e