Malicious PDF — malware analysis report

Static analysis result for SHA-256 c56daa44b04d64ef…

MALICIOUS

PDF

115.5 KB Created: 2021-09-13 12:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 13509695c1bcc176d71d5ec2db25dc74 SHA-1: dbd2d8ca27f5312e9d40491adb1bd9670c917d81 SHA-256: c56daa44b04d64ef3faa1af99e63e22dd1126b7f60ef105cb6b3d32033d0b9b0
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with a high-confidence heuristic identifying a link to an algorithmically-generated URL, suggesting a malicious intent to redirect users. The presence of multiple disposable hosting links further supports this, indicating a link farm designed for phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://philabc.ru/uplcv?utm_term=chimera+ant+full+episode PDF link annotation
    • https://thefertilizergranulators.com/d/files/58679757607.pdfIn PDF document text
    • http://originalavto.ru/userfiles/file/sarekudimamep.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/lemaluvikudavaneduma.pdfIn PDF document text
    • http://ekstelekom.com/userfiles/file/xiwara.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/50955106158.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/20205589238.pdfIn PDF document text
    • http://pokebarslo.com/uploads/files/subep.pdfIn PDF document text
    • http://jezirka-biobazeny.cz/UserFiles/File/53121270251.pdfIn PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/34511569362.pdfIn PDF document text
    • http://amghanoi.com/images/ckeditor/files/99808890940.pdfIn PDF document text
    • https://aznamaste.com/ckfinder/userfiles/files/22668776616.pdfIn PDF document text
    • https://pankajplast.com/ckfinder/userfiles/files/tokabumamuvinisuzilago.pdfIn PDF document text
    • http://finpacecuador.com/userfiles/file/46504471202.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/f431cfd68ce8498a5fa48c84673c682a/54686784974.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/7176726205.pdfIn PDF document text
    • http://krr-nfe.com/suratnfe/UserFiles/File/30198135503.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/nojatem.pdfIn PDF document text
    • http://tulga.ru/editor/files/75025940126.pdfIn PDF document text
    • https://fresh-cherries.com/ckfinder/userfiles/files/52207188297.pdfIn PDF document text
    • http://stavclearing.ru/upload/files/61692313056.pdfIn PDF document text
    • https://chataigne-cevennes.fr/imgs/files/ganitadubo.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/58881459197.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/35911951117.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/bivhjsgv7f92kk9kth5710gjv7/28841768183.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/35676547033.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_off00015cab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15CAB 19136 bytes
SHA-256: cf28f81139fe674bb8594f6286de8cfcd95c0b9554b421819ff760868f4eaa96
font_01_sfnt_off00018f0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18F0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001a723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A723 10896 bytes
SHA-256: e5b73f176884526bd807d25cfe0c047125e0017d33477e6ab54ed17c28ef0bac