Malicious PDF — malware analysis report

Static analysis result for SHA-256 9728694dbfced359…

MALICIOUS

PDF

71.8 KB Created: 2021-09-28 04:04:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4b6f5002107361d24e42ec4d4d70ca17 SHA-1: 9fae0463b770b31dfd9667c865610aa88b829897 SHA-256: 9728694dbfced3596814562968a00b868d93f377fa911e8fa2f6c6272ec23c3f
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to disposable hosting and are presented as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this assessment, suggesting the document's primary purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://inwebjor.ru/uplcv?utm_term=conditionals+exercises+0+1+2+3+mixed PDF link annotation
    • https://gamedunyasi.com/calisma2/files/uploads/nafoselejikegiwezunilav.pdfIn PDF document text
    • http://unstitchedfootwear.net/files/file/35866119083.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614c99d7e80b7---49550957102.pdfIn PDF document text
    • http://ideviceplus.be/app/webroot/files/userfiles/files/78886593390.pdfIn PDF document text
    • https://yenhuy.vn/upload/files/mizope.pdfIn PDF document text
    • http://kirche-treuen.de/UserFiles/File/fuxewavepokakivexoxumuvo.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/jixovafuwufigebosufer.pdfIn PDF document text
    • https://hankilfood.com/upfile/files/42706416013.pdfIn PDF document text
    • https://kominove-centrum.cz/media/files/file/lonoxaxadutuvek.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/81955935282.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/seteralo.pdfIn PDF document text
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sipazugunudolakos.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/dumozoxowisumukexes.pdfIn PDF document text
    • http://wwstationery.com/files/file/19852663482.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/74650681083.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/namivik.pdfIn PDF document text
    • http://topliving.sk/userfiles/file/bovapezolumev.pdfIn PDF document text
    • http://zeminyerkaplama.com/upload/ckfinder/files/34543242017.pdfIn PDF document text
    • https://cjsc.se/ckfinder/userfiles/files/62926837759.pdfIn PDF document text
    • http://land89.com/ckupload/files/36694953891.pdfIn PDF document text
    • http://cermak-expo.cz/data/files/file/71279440896.pdfIn PDF document text
    • https://kawanmto.net/contents/files/juxivenaxekororimuriloxa.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/j87f4u1cis0oh6a2lnh1h1siv3/6612705717.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_off0000b051.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB051 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c863.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC863 18448 bytes
SHA-256: 608820a796fe1de2b41a374665a8396ff38e492c60662e6096762a25dbc45bcc
font_02_sfnt_off0000f7e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7E2 11132 bytes
SHA-256: dd617821309e765af6b536b66cc4f052b263e17e8fa1b6bb43a5463b4018bb27