Malicious PDF — malware analysis report

Static analysis result for SHA-256 a359a89f5f5f98d1…

MALICIOUS

PDF

74.2 KB Created: 2021-09-14 01:56:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 49488857d090111d923f7357b4320296 SHA-1: 5d431a965d427ed13e89a5ac476d5ab9d1bf6056 SHA-256: a359a89f5f5f98d11a3f026f72cd4b6b6a2fb8dfb8fc894f1c9496775570d2fb
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external PDFs hosted on various domains, many of which appear to be part of a link farm designed to obscure the malicious intent. The ML classifier and ClamAV detection strongly indicate malicious content, likely a phishing or trojan payload delivered via these links. The presence of embedded JavaScript, though obfuscated, suggests an attempt to execute malicious code upon opening or interaction with the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 https://gs-hemeringen.de/ablage/userfiles/files/salesugudowo.pdf In PDF document text
    • http://gniortho.com/files/Upload/file/lidologexuwogof.pdfIn PDF document text
    • https://casaalu.com/luutru/files/tipetokujanufuvobike.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/14609545418.pdfIn PDF document text
    • http://slbreakingnews.com/ckfinder/userfiles/files/sekep.pdfIn PDF document text
    • https://atlantidegattico.it/file/runawafotidegovogowa.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/geroni.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f09dba6ca0---mipaxebogekoji.pdfIn PDF document text
    • http://irvinenott.co.uk/ckfinder/userfiles/files/13198480097.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/tutorig.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/popadoporazikojumavapom.pdfIn PDF document text
    • https://skywaytravelandholidays.com/ckfinder/userfiles/files/suxusapedep.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/54000413916.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/61356625370.pdfIn PDF document text
    • http://www.mecateengenharia.com.br/ckfinder/userfiles/files/56764107193.pdfIn PDF document text
    • http://sd-admin.fazendapenaazul.com/ckeditor/uploads/files/bisonawobopubevon.pdfIn PDF document text
    • https://ecoverservice.be/gallery/file/zuloda.pdfIn PDF document text
    • http://aptekadc.pl/userfiles/userfile/putusufanivujakowofupujo.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/sirigutofunupusat.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/19130896245.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/98658341150.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/b7ae8613d0d61db26019a2f63a29e616/tafusasevuwawowuxus.pdfIn PDF document text
    • http://mrs-edu.com/sribati/editor/uploadfiles/11251479960.pdfIn PDF document text
    • http://tuzy.pl/Upload/file/12716919363.pdfIn PDF document text
    • https://starfoil-mail.nl/uploads/wysiwyg/20017437110.pdfIn PDF document text
    • http://ipublicity.cz/data/file/runuxowax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=cambridge+ielts+4+pdfPDF 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_off0000bd71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d588.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD588 10864 bytes
SHA-256: a356261fbc96c17f0b669b2a2c1b3c54735faabb63618a815eda4a023b476e38
font_02_sfnt_off0000ee39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE39 17732 bytes
SHA-256: 7762e734d2c1c09313c7ec66fa310004b93d9d805a26fc09ff1c6ed062cb1bb3