Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f9b7b96e403196d…

MALICIOUS

PDF

71.2 KB Created: 2021-10-03 14:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 86d0d396bb15da209c0909c4cf5af392 SHA-1: 28846c1f909313c1541c6e7fc003d2ab6089b2fb SHA-256: 9f9b7b96e403196d8e4450675e06efae983564c6a04ca0f148f5825a982e4aaf
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Additionally, multiple heuristics indicate the presence of a link farm pointing to compromised websites, suggesting an attempt to redirect users to malicious content or download further payloads. The ClamAV detection and ML classifier strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.atccs3.it/atccs3/fckeditor/editor/ckfinder/userfiles/files/xowefu.pdf In PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/68589603972.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358b76cc896---71533575223.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/josafumolifisotimaze.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/c46726c74fea1df04b752b6f36d7ba09/72694356726.pdfIn PDF document text
    • https://artedeeducar.com.br/ckfinder/userfiles/files/fameroxazovarikuni.pdfIn PDF document text
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pipozapopuna.pdfIn PDF document text
    • http://gospelpour100voix.com/fichiers/newsletter/file/robovoparozawavotur.pdfIn PDF document text
    • http://kpghomerepairs.com/uploads/image/files/65156454361.pdfIn PDF document text
    • http://prestopc.it/upload/file/80721571688.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/jetiwijuborokenilet.pdfIn PDF document text
    • http://jinanxintiandi.com/userfiles/files/fapepotijobawafuroxo.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/43890301446.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109021847175343.pdfIn PDF document text
    • https://totounited.com/contents/files/74500799626.pdfIn PDF document text
    • http://gok-maciejowice.pl/js/ckfinder/userfiles/files/mepetajemegozuvopetexi.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/lakovufufitugere.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16133e98b2727b---fubilejon.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1632463988.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/dfd40f5cb4e2b02b0d07f77c113e1fdb/megagirugizutita.pdfIn PDF document text
    • http://huijingweb.com/upload_fck/file/2021-9-23/20210923204500362329.pdfIn PDF document text
    • https://mosallaesf.ir/uploads/ck/files/sulitefoporavinelunaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=gastric+sleeve+gastric+bypassPDF 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_off0000b187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB187 10684 bytes
SHA-256: 66c8ae2f5986e6a01ca369758af2fc85c5c68e3c4e25a1ebb2417a553e15de8f
font_01_sfnt_off0000c9fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9FE 17952 bytes
SHA-256: 48812961341793b4818cf5bc6ef9bc688cf549d98c946e2ba0e27a4b27fd3213
font_02_sfnt_off0000f778.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF778 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1