Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c443c7f1c5908a6…

MALICIOUS

PDF

81.4 KB Created: 2021-09-05 09:06:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2b28b7ba23239b7ba6b5f67eb82589c5 SHA-1: 3f366dc3c4a8492b822e7c2cf83dd90c7723178a SHA-256: 6c443c7f1c5908a68064265e6a0665e63eccf16fa72064e2a9b0e34801c68a64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of the links and the PDF structure point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 http://change-sexy.com/files/files/xiboxiwapi.pdf In PDF document text
    • http://wasserburg.pl/userfiles/file/zutugiwerenisubonagifu.pdfIn PDF document text
    • https://airbays.com/userfiles/file/92984752292.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/243c53516069dac057c3aef06ebb0fb6/lixifutirumegurozuxevup.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f986ebee412---nasulipav.pdfIn PDF document text
    • http://geopraxis.it/userfiles/files/lufirijoraso.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/8179187265.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/52196047146.pdfIn PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/36919249799.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/67621581858.pdfIn PDF document text
    • http://purepoem.com/resource/docContentImg/file/2021-08-13/f05cf287d602a2fcbfbb0a907bd0c331.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b865ebdf024---63375990628.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/pke323il1jepepe9mb8j5ldqc5/dorurudifelarovu.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/sls8g79ilj51m8so7br6i8f0h5/29581871021.pdfIn PDF document text
    • http://rogersdesignhouse.com/uploads/files/levejexevewarosawib.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/87990350891.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/78587aae614c88cbd19f92c75f58dbaf/liweku.pdfIn PDF document text
    • https://roeveragri.ac.in/wp-content/plugins/super-forms/uploads/php/files/7e1ed2b26d58b667db029009d4b2e774/sutifujutewunogosupeb.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/badoxorabukufifexujawi.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/52c672e10b62f3772c165e5ff1105ad4/42242268577.pdfIn PDF document text
    • http://bantinnhadat.com/users/files/88976965073.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e05d9129f---notiz.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/q1m7kns5kvfdk20rthnchl91qi/47654419981.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f63e858f08---78776908982.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/beraxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=atlas+of+suturing+techniques+pdf+downloadPDF link annotation
    • http://cluster006.ovh.net/~greeters/be/ckfinder/userfiles/files/xubig.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_off0000d41c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD41C 11212 bytes
SHA-256: 9cf6282fe2731841c9d0415563567f9f63ff3c124c33c4babb60fda1624ccdf8
font_01_sfnt_off0000edd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105EA 18860 bytes
SHA-256: 099816ea35398f67161a3383fad53b5b7635870f0dc6390a5b0902966704a20e