Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b1a9ff84a097cd1…

MALICIOUS

PDF

70.4 KB Created: 2021-09-25 15:30:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b81ba6a36c9d7cb41d34df2ed17d986a SHA-1: 40ec2cf0a6ba5bfd41bb63e9cfd03d36a6cc496c SHA-256: 0b1a9ff84a097cd163d628744bf0cf054b9fb5667ffab7b591572983dbd28d38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads and disposable hosting. The primary purpose appears to be directing users to external sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.jasolasia.com/image/upload/File/23237136668.pdf In PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_16_06_07_10_6504.pdfIn PDF document text
    • http://gpkoaee.ru/ckfinder/userfiles/files/96944680587.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210912_67D4A01FADBE0A4E.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/28402782913.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/93261264233.pdfIn PDF document text
    • http://grupophi.es/uploads/files/diletuja.pdfIn PDF document text
    • http://ipublicity.cz/data/file/91599538472.pdfIn PDF document text
    • http://hwayinn.com/image/files/20210923_192215.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/balivunuseguwuxawakukeb.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2b743f5bd---87089185184.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/zaxagabatigeputinura.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b3ca994f81---92196714297.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161486a50bb57f---19555436733.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/55981415672.pdfIn PDF document text
    • http://wx-test.com/upload/ckimg/files/202109211237108102.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141feda8bb7e---moriwekifesix.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d013daea4e---60855762707.pdfIn PDF document text
    • https://brakos.it/file/29339695541.pdfIn PDF document text
    • http://techsystem.gr/data/uploads/ckeditor/files/pirinavurofodifisumufud.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/damadomitub.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/tupaderux.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/b23f1c1475c6eddfcb3790b976721d98/36722358276.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/degubuwuvolufefoxivuwokup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=dna+to+rna+codon+chartPDF 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_off0000b328.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB328 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB3F 10028 bytes
SHA-256: 0284f5c1b45771ba6b2370ed12f0199d5ad3355291e175ba5a422b19c00bc68e
font_02_sfnt_off0000e169.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE169 16720 bytes
SHA-256: 233377a0332e644a7f307e38db3c9bcfe57804fc34374a37e7cf5cd941fde9ed