Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c2437bc23aeec49…

MALICIOUS

PDF

85.8 KB Created: 2021-09-20 09:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 79f2f12415758718de014907d1d661b7 SHA-1: bd38ddbef3ba7e056234501a55c31bf16c822972 SHA-256: 0c2437bc23aeec49af765bf8aeffcc1a5fab1a0009259fc8f88c3c12ea642f9b
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous URLs were extracted, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded links are consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://inwebjor.ru/uplcv?utm_term=top+10+android+games+offline PDF link annotation
    • http://parmalab.it/userfiles/files/46787012729.pdfIn PDF document text
    • https://nmg.lv/img/uploads/files/7634315685.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/b39e1cd69b6f93965067d6c640ec42de/5721502742.pdfIn PDF document text
    • https://ceccarmehedinti.ro/userfiles/file/33404466419.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/88163334008.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/21081083063.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/gisasajovef.pdfIn PDF document text
    • https://webrekruit.com/php_codes/Scott/VieauAssociates/code/userfiles/file/57037467285.pdfIn PDF document text
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/dikabepiturudo.pdfIn PDF document text
    • http://zs-oilfieldequip.ru/d/files/23173969062.pdfIn PDF document text
    • https://rubfila.in/files/file/tijexufogesotida.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/161337b8c2aed5---17974791349.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/44752579916.pdfIn PDF document text
    • https://marathonlaval.com/userfiles/files/66725596182.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16130ee68728a6---dozokeguran.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/losupifabedeberulel.pdfIn PDF document text
    • https://diarch.in/WYSIWYGImage/file/nuraboxariguwokunajaku.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d435a3b2a7---58635140390.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/29639940791.pdfIn PDF document text
    • http://hasomedia.com/userfiles/file/wefiwejexumunegefifo.pdfIn PDF document text
    • http://tayles.com/uploaded/kixumagugapenopijavij.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/63033187169.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/1138195363.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-9-13/20210913050305659153.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/2021913_224938_940.pdfIn PDF document text
    • 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_off0000ed96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AD 10880 bytes
SHA-256: 5bf6d02c293e6e01076fe7e935cad5b4464ad0554738060a2c70bad3c4ff0956
font_02_sfnt_off00011e90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E90 16696 bytes
SHA-256: ae7370020bab9bcfa914b9e79d3275a7f4f948ff1806043482e79a342fa2f65c