Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c83b6983a300726…

MALICIOUS

PDF

69.8 KB Created: 2021-09-20 15:14:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6e2a2dc6cb9e99d37f8f14cb036e7df5 SHA-1: 2ec3ccf6acbcca32b4625e2e7dffb03215d0d2e7 SHA-256: 8c83b6983a30072633dc1cfeed4756b175bf2414b8f1de8ee9bc8ba30b2844ec
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 compromised websites or disposable domains, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://infrive.ru/uplcv?utm_term=logo+quiz+answers+level+3 PDF link annotation
    • https://krygina40.ru/UserFiles/File/66515639086.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/25498600755.pdfIn PDF document text
    • http://www.dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/48533335552.pdfIn PDF document text
    • https://ver9.sonikgps.com/ckfinder/userfiles/files/19060055102.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-19/20210919074643134897.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/s037nclet30905tee5qnfuig87/berajusodip.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/kiduwutaf.pdfIn PDF document text
    • https://khanikango.in/file/71614483461.pdfIn PDF document text
    • http://etkindenetim.com/resimler/files/84443565939.pdfIn PDF document text
    • http://htwy.com/upload/file/6835584507.pdfIn PDF document text
    • http://wajl.net/img/file/20219160263.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/godegenovimu.pdfIn PDF document text
    • http://ministryofrum.com/memlogos/file/lodunula.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/8f9a2939ef8bf6344ec87fb7ec05e545/19936202736.pdfIn PDF document text
    • https://kebecelectrique.com/upload/editor/file/31443303558.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/sezedalefufetogepesigap.pdfIn PDF document text
    • http://minerva-collection.net/files/files/2351300164.pdfIn PDF document text
    • http://queensparkview.com/image/upload/File/gunobibanibiz.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147d92fc5568---zoveruleledomataja.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135675cc0a88---12614334473.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/91892789379.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/kinukufodanonuzedopujej.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/zukemus.pdfIn PDF document text
    • https://jungleflightchiangmai.jungle-flight.com/Uploads/files/11421901026.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_off0000b2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2DD 15108 bytes
SHA-256: 3efe23090ea636cfadd284034b8369faabca01854bd035a8856e28aa12558a3d
font_01_sfnt_off0000d93d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD93D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF154 10772 bytes
SHA-256: 252ecea80c2342dcfc0d6c119315d8a8f9c78ae38add2a5cf2ea900536a16d1e