Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b388ed027ce1c4a…

MALICIOUS

PDF

81.8 KB Created: 2021-09-08 20:12:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 88c239f51a9b2437f9e8a47a7e4802a0 SHA-1: 0d010b208465fd4cd3dc9f39459bb7b4e3075dbf SHA-256: 9b388ed027ce1c4a9d88ac2cf5081b7c23f138b965793bc797492e5acd750756
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The ML classifier also strongly indicated maliciousness. While no scripts were directly extracted, the PDF structure and link farm behavior suggest an intent to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 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 https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161341514474e5---parexarovanavelovepat.pdf In PDF document text
    • https://aromamarketing.md/img/files/74663288206.pdfIn PDF document text
    • https://anitt.in/ckfinder/userfiles/files/72890303986.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/zofawe.pdfIn PDF document text
    • http://www.serenissimaservizi.com/files/67701727961.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/53826870536.pdfIn PDF document text
    • http://ciaooo.ru/uploades/userfiles/file/66816898332.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612fdcd5099e3---20930933164.pdfIn PDF document text
    • https://jcmimoveis.com/userfiles/file/4022338326.pdfIn PDF document text
    • http://wwsm-hk.com/files/file/gulepadesofum.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/72341435908.pdfIn PDF document text
    • https://ximatinhdongnai.com/app/webroot/files/images/pages/files/devozefududimesugiv.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/logonilejonuninatufaj.pdfIn PDF document text
    • http://bobhendrix-law.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/86658004375.pdfIn PDF document text
    • https://km2804.com/ckupload/files/61309509300.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210908205948.pdfIn PDF document text
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/41190466784.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-9-1/20210901115449917286.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/68270271467.pdfIn PDF document text
    • http://findingthegrey.com/userfiles/file/xotiwabopuw.pdfIn PDF document text
    • http://tabletopad.com/images/file/guzenisofumamorulajuv.pdfIn PDF document text
    • https://gionggiacam.com/ckfinder/userfiles/files/63902251742.pdfIn PDF document text
    • http://tvsatkrosno.pl/userfiles/file/mobesadivulirev.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/161334e9c3177c---40969529771.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/pajufubek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=mbti+test+results+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_off0000dd13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD13 17472 bytes
SHA-256: 70622f59670602578eb05fe9c5e6c0caaa051448b9dd53fa15478a6e322d5c8c
font_01_sfnt_off00010a3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3F 10340 bytes
SHA-256: 3a33e9f7e632cb05c6f6f2cd6ede55fbcaa69e3e13b90649b5402f704facd79b
font_02_sfnt_off0001217f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1