Malicious PDF — malware analysis report

Static analysis result for SHA-256 af5785cb1829699a…

MALICIOUS

PDF

85.9 KB Created: 2021-09-22 15:54:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0c16a3d04bb686e0d7d1e7fcb71beffc SHA-1: 445e03447f164793943d014a31e91e8f840f21c1 SHA-256: af5785cb1829699a794afacddaf8927374224dc63a73904682823a1238aac6b9
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple external URIs and link farm heuristics supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://kimyasaldubeller.com/upload/ckfinder/files/jesidezulim.pdf In PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/79119120691.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/jizotaluxunowema.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/6781258181.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/l7n6hv2h9iklsihlvt6bihdf89/xasisat.pdfIn PDF document text
    • http://showdoimovel.com/files/files/46418375041.pdfIn PDF document text
    • https://amoslodge10.org/ckfinder/userfiles/files/457935351.pdfIn PDF document text
    • http://satakantaresort.com/user_img/files/dezozopejedefusurikes.pdfIn PDF document text
    • http://mediedil.eu/userfiles/files/jimimesuroxixudatebeto.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135ce8416d37---vusixazozifej.pdfIn PDF document text
    • http://e-district.org/userfiles/file/lutabe.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/209d8850501139b0ccbdb8c7419424d2/tekafu.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210901171023075.pdfIn PDF document text
    • http://alliance-ic.ru/uploads/file/luvalikoluzusa.pdfIn PDF document text
    • http://larben.cz/media/images/upload/file/falare.pdfIn PDF document text
    • http://auswallendorf.de/userfiles/file/jerib.pdfIn PDF document text
    • https://dianthusindustrial.com/resimler/files/somiwavidilafoj.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/fedejivorivilufe.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/negekazo.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/3115175525.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/71523870302.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=search+location+in+google+map+androidPDF 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_off0000e83c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE83C 18292 bytes
SHA-256: 6221660db01a9a8a00e756d03a8f8d16cb6fd040dda5f0bcd05236b7b1e756d2
font_01_sfnt_off000118f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118F9 10868 bytes
SHA-256: ad00362708dda0b2b7ae35d23cd4317f0d316c4ed72ee86c88dec2549e2fd78b
font_02_sfnt_off000131a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1