Malicious PDF — malware analysis report

Static analysis result for SHA-256 998917c928e1bf6a…

MALICIOUS

PDF

85.4 KB Created: 2021-09-20 06:52:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2f1d99b935ad365c61068a5c71d0d9f6 SHA-1: c6e831bca3527e54724bc27df9ab016f0ab46574 SHA-256: 998917c928e1bf6a459098dca2bad41b3a112a954b34faab22a7ee04eb0d0bad
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a high heuristic indicating it's a link farm on disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pistant.ru/uplcv?utm_term=how+do+i+unblock+a+number+on+my+android+phone PDF link annotation
    • http://ktcz.eu/files/files/fijogima.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/60168241877.pdfIn PDF document text
    • http://hotelrefah4ter.ir/basefile/hotelrefah4terir/files/93717380716.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130b209e24e5---solekujoxomeza.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/32022117657.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013new/admindia/ckfinder/userfiles/files/laripowumegosuxezuxefe.pdfIn PDF document text
    • http://myconnect-thailand.com/image/upload/File/71099545869.pdfIn PDF document text
    • http://modellszerviz.hu/userfiles/file/rimajekugolojezapif.pdfIn PDF document text
    • http://babyindex.nl/images/uploads/vosufaderarigikekefulopa.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/67570543928.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/87651441696.pdfIn PDF document text
    • http://otworz-biuro-podrozy.pl/userfiles/file/lozikegev.pdfIn PDF document text
    • http://ttccid.com/userfiles/files/zoxedofudivovad.pdfIn PDF document text
    • http://www.neoneofitou.com/ckfinder/userfiles/files/biwixixet.pdfIn PDF document text
    • http://dgone.kr/userfiles/file/20210919162312.pdfIn PDF document text
    • http://immobilier-valence-agen.com/userfiles/file/xebiludotogodaxuluto.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/a47e7ac5fe01721f18d6e00ae0ca790d/kakevi.pdfIn PDF document text
    • https://icoachyou.biz/images/ckeditor/files/83654689695.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/jimiv.pdfIn PDF document text
    • http://aostavet.it/userfiles/files/zizoxaxamuterum.pdfIn PDF document text
    • https://sysyanginguvenlik.com/uploads/files/vunetanoxuvepemopokonul.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/kezogovalezok.pdfIn PDF document text
    • http://indemo.pl/Image/files/wifagitakoxuvafu.pdfIn PDF document text
    • https://ichapps.peaceofworld.com/ichapps/ckeditor-ckfinder-integration/uploads/files/18543518086.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/nuzofedalazolaxagan.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_off0000e73a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE73A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ff51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF51 11036 bytes
SHA-256: 53b503e8686ae673e8bf0fd880dc06ee5521cc655462615d4c5c28e644c9b932
font_02_sfnt_off00011886.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11886 18048 bytes
SHA-256: b867cc53b5a49d0923ce8c67157b88c300e398a0d56a955d2aef476f93306f28