Malicious PDF — malware analysis report

Static analysis result for SHA-256 a79435a098e23585…

MALICIOUS

PDF

85.8 KB Created: 2021-10-05 22:58:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 616553e273885dadaa0d131d5d9eb515 SHA-1: 543b6e00d1129746cacf2541a6064b74d190d28f SHA-256: a79435a098e235850b45f60df9902fb9cdc8c1218c890e702a30e094b636d801
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. The embedded URLs are designed to redirect users, likely to phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://okzawidow.pl/img/upload/files/87152524811.pdf In PDF document text
    • http://sieuthibds.net/images/files/30747694245.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/10d0f64ee4ac06a705b681508b09e29c/21427937715.pdfIn PDF document text
    • http://vakoplus.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/virodukumaruxi.pdfIn PDF document text
    • http://colokit.thienlonggroup.com/Images_upload/files/zasisap.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/sopm89gi4e8sg0nnnctvmbhged/rabamakasokaki.pdfIn PDF document text
    • http://danangsculpture.com/uploads/image/files/lanasidegawoxawotema.pdfIn PDF document text
    • http://murasakijr.com/uploads/files/8614713506.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/pupuposavat.pdfIn PDF document text
    • https://franchisevisions.com/broker-site/files/files/5468253871.pdfIn PDF document text
    • http://toflight.mobi/attachment/ckeditor/files/bfd44039d02c600740bf84d6897d25a2.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/5536866068.pdfIn PDF document text
    • http://mvpbuilding.com/userfiles/file/47732949490.pdfIn PDF document text
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/64215184529.pdfIn PDF document text
    • http://dream-mebel.com/pic/file/53072403710.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/oq6ufojle1svgglq16hoe801jv/potizapisebidolugusar.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/mevalimisiwidifewofev.pdfIn PDF document text
    • https://nocnepal.org.np/ckfinder/userfiles/files/87036760984.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/taxaginam.pdfIn PDF document text
    • https://nidi.mk/ckfinder/userfiles/files/75795469905.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/buluvipidenorikeku.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/c35354fad7775c6cf0fa4b77fb9364bf/96383596489.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/pasol.pdfIn PDF document text
    • http://atsrealtyvietnam.com/upload/files/26122352460.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/walobopowapimanoge.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=a+taxi+driver+streaming+onlinePDF 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_off0000e798.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE798 10740 bytes
SHA-256: 0faf9ba0719aefcb656222c66b5e7c531471d870a0ea087adb033cc47f11526b
font_01_sfnt_off00010010.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10010 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11822 19228 bytes
SHA-256: 51b9e074c99bd0042c353b2b4ee7dc1f05cfefcccaa1f23cf08ddd7acbde706b