Malicious PDF — malware analysis report

Static analysis result for SHA-256 d51cb9e2d84cf7da…

MALICIOUS

PDF

84.4 KB Created: 2021-09-19 04:32:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 02c6fe546dc2db8ba34f0756dbb78d6d SHA-1: 873567d2e33babdaf286ccd6bfb02e70725a4299 SHA-256: d51cb9e2d84cf7daa56199740b10edc0e51984341cd6032a0cd0f3cfbac38d21
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or malware distribution lure. Although no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attack pattern involving directing users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://barcelonacentremedic.cat/files/galeria/files/67310916412.pdf In PDF document text
    • http://datavincity.com/uploads/ckfinder/files/vijixolemejisaz.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/lagiwisariwamopafekodezu.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/22171720876.pdfIn PDF document text
    • http://somsit.com/ckfinder/userfiles/files/79060319105.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/redikijukoxufeteketen.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/da16rrsoo5ppgmrhbph7l2lr17/silasitadojixoguliw.pdfIn PDF document text
    • http://alexdisinfestazioni.com/userfiles/files/bibonef.pdfIn PDF document text
    • https://agronlogistics.com/userfiles/files/pigor.pdfIn PDF document text
    • https://fishboat.hr/files/55855132119.pdfIn PDF document text
    • https://urbanlivin.lu/userfiles/files/98190478347.pdfIn PDF document text
    • https://alshuka.ps/ckfinder/userfiles/files/652127107.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/94607712783.pdfIn PDF document text
    • http://yuli-china.ru/d/files/82168827229.pdfIn PDF document text
    • http://guanzhuli.com/userfiles/file/pusojokiriwopixoxekugo.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/wopizirikogabexejo.pdfIn PDF document text
    • http://drentmedischadvies.nl/uploads/files/linok.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/nagolejutiwukamigezuse.pdfIn PDF document text
    • http://magooferta.pl/uploads/fck/file/refukonufekorata.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143a52ab9c06---debem.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/galab.pdfIn PDF document text
    • https://lalicorne-hotel.com/userfiles/file/ditubov.pdfIn PDF document text
    • http://pvvc.cz/files/wijulomakeb.pdfIn PDF document text
    • http://etcpremium.com/userfiles/files/bewowoludiw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=free+tv+shows+apkPDF 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_off0000e245.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE245 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA57 19288 bytes
SHA-256: 74cd627b694462291a4d05503c9f59ecce777922e6d833806a65db12c6714df5
font_02_sfnt_off00012c5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C5F 10328 bytes
SHA-256: 449680aa0afc568e39f6543b536c0d462094d058d8f23d9ff2e5cf715e3aa2c6