Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf0387deddc51be8…

MALICIOUS

PDF

70.0 KB Created: 2021-09-27 01:54:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4ea008cf9ab285ad3c339b2994501963 SHA-1: ae24e3eb27052aa4457fe1faa07a8872004197c9 SHA-256: cf0387deddc51be8777fbb2e08290b449e17e88d7ca701a7e4f842eabf6da395
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to PDF files hosted on various domains, some of which appear to be compromised CMS upload directories. The document body is unreadable, suggesting it's not intended for human consumption but rather to host these links.

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://apvn.info/userfiles/file/nudepipoliwaj.pdf In PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/161489f9c9ee2c---foxizumovakurufuzalibaf.pdfIn PDF document text
    • https://mobilpetrol.olajpark.hu/files/files/wojizubasusunivixe.pdfIn PDF document text
    • http://dzirerealtors.com/uploads/pupilidadokumodiwed.pdfIn PDF document text
    • http://vizesblokk.hu/files/file/buxurudisipavisajotul.pdfIn PDF document text
    • http://zge-led.com/luodan/images/userfiles/file/38031361638.pdfIn PDF document text
    • http://musik-fachberatung-neumarkt.de/images/uploadedimages/file/widut.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/vikasiruzonorarajuwawig.pdfIn PDF document text
    • http://airmon.hu/images/files/24154287018.pdfIn PDF document text
    • https://partnyor.az/userfiles/file/zonomofojovewijeji.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614dcd805226e---12698429249.pdfIn PDF document text
    • http://abdon.madteam.net/ckfinder/userfiles/files/dudomeditijovafopemawew.pdfIn PDF document text
    • https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/sesekamezililaxiwexiso.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/i8j3j500ckupbqnbhou4t9k60m/ruwitafesowumabatagixutof.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/vogalojazitotuk.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/xufomar.pdfIn PDF document text
    • http://xfswchem.com/upload/files/84394419025.pdfIn PDF document text
    • http://czernavendeghaz.hu/admin1/file/63522257072.pdfIn PDF document text
    • http://mcutech.net/upload/2021/09/file/16309882671475866926.pdfIn PDF document text
    • https://havadisname.com/upload/ckfinder/files/mitomovejamiloriluxigar.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/wipilagezigeko.pdfIn PDF document text
    • https://jetaime-shop.dvsportbg.com/files/vorumojodufokasutitese.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f5541eabd5---zakazon.pdfIn PDF document text
    • http://clingac.es/d/files/kavejufexowekobanidozul.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles/files/zokefegatana.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=rdxhd+watch+online+movies+free+and+download+it+freePDF 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_off0000b40d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB40D 11040 bytes
SHA-256: b436d982cd9cd85ad2ba8151e91f31c266383cf7c33c49f4f29fec64d3c1bbc9
font_01_sfnt_off0000cda3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDA3 14484 bytes
SHA-256: 060431c66d4de0f4bd4aec1ddb82ed5c4f4dbc814948dd24144ede5ac8cf3566
font_02_sfnt_off0000f1cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1