Malicious PDF — malware analysis report

Static analysis result for SHA-256 38fff603b9750d46…

MALICIOUS

PDF

92.0 KB Created: 2021-10-04 13:10:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: f8d1db43bbf68c07b8964e8c35c45c94 SHA-1: 90fdee584aa62452201135f69c68d1e904fe90bc SHA-256: 38fff603b9750d4629e9e615bc0184b2d961142dbab02f830594a26c96fdc83e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting and are structured as link farms, indicating a likely attempt to distribute malicious content or phish for credentials. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM strongly suggests this is a link farm designed for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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.
  • 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://irlanc.ru/uplcv?utm_term=red+mark+on+baby+stomach PDF link annotation
    • http://oresteruggiero.com/userfiles/files/54465721927.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/xoramawubekabu.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/zenugebapiwowexusodo.pdfIn PDF document text
    • http://ride-on-earth.com/images/blog/file/55826105282.pdfIn PDF document text
    • http://aromamahabaleshwar.com/ckfinder/userfiles/files/9742953664.pdfIn PDF document text
    • https://deltarents.com/upload/ckfinder/files/69008090716.pdfIn PDF document text
    • http://tryinvest.eu/userfiles/files/45377303130.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/sidagimorixur.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/nejenodajiliginibarome.pdfIn PDF document text
    • https://parlagame.com/calisma2/files/uploads/13396453133.pdfIn PDF document text
    • http://hurtglass.pl/upload/file/guvafapesufijezupoje.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/vezubewizemoxejo.pdfIn PDF document text
    • https://vietucmould.com/img-vietuc/files/65702220078.pdfIn PDF document text
    • https://kuepancong.com/contents/files/94478040061.pdfIn PDF document text
    • https://arenerachicamocha.sinecsas.com/ckfinder/userfiles/files/fosomusapawufututejuduvaz.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/13185733922.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/8efda0f93f462be3bfe222cae9b8b835/jofijofixaf.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1613468e767af6---57477887823.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/fazovefulolodotofunonuju.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/94701242698.pdfIn PDF document text
    • http://www.look4job.gr/images/_user_na/file/gebunivexak.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/nekesadewazamemoxorafako.pdfIn PDF document text
    • http://webcertain.ca/contentupload/fckeditorUploads/organization_/file/dagavetufupexu.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001008d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1008D 19080 bytes
SHA-256: c0757e3dafef48751bcc2e9266185099ebbdfa42a8fcffe52d057cfbad906737
font_01_sfnt_off00013190.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13190 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000149a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149A7 10888 bytes
SHA-256: 433cdac94ce5dfdb77273a403a818eeb870e14aa6f8c7b62b913c97a3fe6c3ac