Malicious PDF — malware analysis report

Static analysis result for SHA-256 86816326ebb76b8a…

MALICIOUS

PDF

87.0 KB Created: 2021-09-10 10:17:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 05f1be5e069bddc21428567726d8f182 SHA-1: b07c19582554e3ffa2269105a397942661b5a8e8 SHA-256: 86816326ebb76b8a0a673b250311fd8c8678df1eac58e06adf5cd070eb31a360
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous external links, with one heuristic specifically flagging a PDF link to an algorithmically-generated URL. The presence of multiple links on disposable hosting suggests a link farm or phishing attempt to redirect users to malicious sites. No scripts were extracted, but the PDF structure and link patterns are indicative of a downloader or phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://ohxto.com/uploaded_files/userfiles/files/ridadutizusux.pdf In PDF document text
    • http://ebiocell.com/uploadfile/file///2021090404132856.pdfIn PDF document text
    • http://peetersinstallatietechniek.nl/upload/files/36474539013.pdfIn PDF document text
    • http://mweb.cz/images/file/bevanuta.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/97563354818.pdfIn PDF document text
    • https://valenciamaids.com/userfiles/files/13848285048.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/wiruwi.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/zuwajo.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///fapirokulopomakudova.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/83105703056.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/72305092751.pdfIn PDF document text
    • http://hndgyl.com/v15/Upload/file/2021932055461003.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/iqcfct8hhsv6fsnu8jgb6vaie0/90934289600.pdfIn PDF document text
    • http://beganijewellers.com/ckeditor/ckfinder/userfiles/files/84264831484.pdfIn PDF document text
    • https://mmtours.si/uploads/gitefedixer.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/44934753826.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/tojijedetasijev.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130f2edc030f---14424419640.pdfIn PDF document text
    • https://rubenoferro.com/userfiles/file/xisafesaruvofitew.pdfIn PDF document text
    • https://edouardweil.com/userfiles/file/vobenimejotelekojevoxa.pdfIn PDF document text
    • https://momsgardenfoods.com/ckfinder/userfiles/files/14157588057.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/25320255765.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021981227457191.pdfIn PDF document text
    • http://ambulatorioveterinariosantanna.eu/userfiles/files/27545736546.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/90080782510.pdfIn PDF document text
    • https://webaprint.be/img/file/17195009821.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=can+you+get+mods+on+minecraft+mobilePDF 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_off0000eda2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA2 11204 bytes
SHA-256: f1b2aeba711fe251b131cb0eb6ab303de8a035599dfa5d8e92c07856ba54124c
font_01_sfnt_off000107b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FC5 17688 bytes
SHA-256: 2c280d57c8c1f7a2c404c75731ddc1d9f42755d9557660fd7b29b0636515b3a0