Malicious PDF — malware analysis report

Static analysis result for SHA-256 17700ad780ba1837…

MALICIOUS

PDF

71.8 KB Created: 2021-09-13 17:35:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 84eae9df3d51270e0284b4a2f203646c SHA-1: c1276d95faffb503779b9f7e932a1d1e1c909bf2 SHA-256: 17700ad780ba1837ff85c7dea4dfc080b6ba269456c59653d1c5fc7fafd98a1d
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://zahrek.com/userfiles/file/maxove.pdf In PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kijodunufabuvunukuwirep.pdfIn PDF document text
    • http://prefinancovaniehypoteky.sk/res/file/vurimofadimusutakemitali.pdfIn PDF document text
    • https://abogadosaccidentealicante.centralcms.cloud/galeria/files/71197942009.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/68315252661.pdfIn PDF document text
    • http://holidayinntorino.com/userfiles/files/9797537070.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/bukigupaf.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/84122103885.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/tidetizanarubapa.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613360bb88d6e---70099458648.pdfIn PDF document text
    • http://technestudio.eu/userfiles/files/babusi.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/joxexeralo.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16136248b9e7ae---fupinagubufurujofibemega.pdfIn PDF document text
    • http://artin-intranet.com/ckupload/files/77326957626.pdfIn PDF document text
    • https://pmcp-avac.com/files/upload-ckfinder/files/feruwaluxeliribidobe.pdfIn PDF document text
    • https://grafconsulting.pl/Upload/file/32571579352.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/78832862239.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ef70cc1b8---65739721626.pdfIn PDF document text
    • https://yennenga.org/business_school/uploads/file/tomipifidusipotutafe.pdfIn PDF document text
    • http://aktien-analyse.de/images/File/71513359720.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-10/20210910183210336219.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///202193112322122.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/67829367695.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=free+android+apps+downloadPDF 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_off0000b755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB755 10352 bytes
SHA-256: ae6b00efeb2be548cd3dcef25326de97a335204f29876638c48e5093a231530f
font_01_sfnt_off0000cec2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEC2 16868 bytes
SHA-256: 111052f81930023ee26a01a1108f18b03e9d85a5d94b7cc39d72ad37bd40f6c0
font_02_sfnt_off0000f9d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1