Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4fcef9d45bee954…

MALICIOUS

PDF

80.9 KB Created: 2021-09-07 13:44:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: af1d44fc0a6700ba7e6ca2daacda1c3d SHA-1: 8db8be013e6a89d6ddf0580615f86ee2c04a8a51 SHA-256: f4fcef9d45bee9547e098bbe3d93cfb7b03339714bfd631a62a80d8b31869a79
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories and disposable hosting, suggesting a phishing or redirection scheme. The document body is heavily obfuscated and appears to be non-readable content, further supporting a malicious intent rather than legitimate document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://holocaustresearch.pl/nowy/photo/file/91575756407.pdf In PDF document text
    • http://dlt-nkp.com/fileupload//file/xopasawisavajon.pdfIn PDF document text
    • https://www.idd.no/ckfinder/userfiles/files/jidudelatimuzubunofuzogul.pdfIn PDF document text
    • https://www.visitrwanda.com/wp-content/plugins/super-forms/uploads/php/files/1b77b1c1870d1abc2d15a2ea2087bb5a/42230780166.pdfIn PDF document text
    • http://blesk-stroy.ru/userfiles/files/tisejeva.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/863e612e9c29560502db04288e463444/wilik.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/dikide.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/a118d91c32f49f0a85d03ddd7ae13b8e/14326384357.pdfIn PDF document text
    • http://kleiberit.ru/files/file/24108208771.pdfIn PDF document text
    • http://quocteanviet.com/img-chamthi/files/kogekinudutanifos.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/65vbl8sejqo6a7b5bsijujg8i3/97755302146.pdfIn PDF document text
    • http://peneleos.pl/userfiles/file/27735624806.pdfIn PDF document text
    • http://di-tech.kr/fckeditor/userfiles/file/56981631556.pdfIn PDF document text
    • https://bamor.org/userfiles/file/zuriralixu.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/visixepawosaxobofe.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160d8d2312b43a---36413778118.pdfIn PDF document text
    • http://iphysiology.ru/upload/fitoxipajupabewuraje.pdfIn PDF document text
    • http://ansatrans.ru/admin/ckfinder/userfiles/files/80174021328.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2b167644d---32302033710.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/43206360268.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16079a89fb4dab---29754680427.pdfIn PDF document text
    • http://qqsbg.net/uploads/file/legimepomoxulam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=singer+8280+prelude+manualPDF 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_off0000d155.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD155 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e96c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE96C 10972 bytes
SHA-256: b39c83b2b6f71eeecd309437e9af41b773040db7e455fc4df5711d9f8ba27bf8
font_02_sfnt_off000102aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102AA 19932 bytes
SHA-256: ec0f211e42251c730d268aed183f721f62fa39c6a994e022d32598fc5f322e3b