Malicious PDF — malware analysis report

Static analysis result for SHA-256 28440a7e2df5fa20…

MALICIOUS

PDF

74.1 KB Created: 2021-09-17 01:05:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 29779e067f369ae527492acf4f46bee7 SHA-1: ade7e93dbe28b8e23fe430d0a86746017a27fbef SHA-256: 28440a7e2df5fa203360486fdef8df860e26ffef747b463c535481c057654e48
134 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, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous embedded URLs pointing to other PDF files hosted on various domains, many of which are unknown or suspicious. This pattern is commonly used for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://girl0229960192.com/upload/users/files/jofazerajidekofuse.pdf In PDF document text
    • https://hoangnhataudio.vn/media/files/46437214559.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161328ae116ad2---xofinisutot.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/66006653191.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/14487668871.pdfIn PDF document text
    • http://defhjdr.friend-match.com/upload/files/35296285346.pdfIn PDF document text
    • http://shophouse.info/images/files/nufivuvopewekaloz.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/11335656138.pdfIn PDF document text
    • http://yarpb.ru/pic/userfile/xupoledotewagosuge.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/bajikumozavofojiregino.pdfIn PDF document text
    • http://pvvc.cz/files/kafarumogodarisudez.pdfIn PDF document text
    • http://carzip.biz/files/uploads/files/fexufono.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210904053106.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/45919851321.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/66479970206.pdfIn PDF document text
    • https://duel.pl/userfiles/file/66164712118.pdfIn PDF document text
    • http://studiophotosfashion.it/userfiles/files/29110889956.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/lsiifsinf75av9qfb4k0mmqpdo/48123914564.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/79414948960.pdfIn PDF document text
    • http://xn--90afqerdlt1f.xn--p1ai/admin/ckfinder/userfiles/files/65479564704.pdfIn PDF document text
    • http://spamsmsgiare.com/media/ftp/file/solawojewurujotirumanaz.pdfIn PDF document text
    • https://kawanmto.info/contents/files/76362421818.pdfIn PDF document text
    • http://police8coop.com/UserFiles/file/43501238007.pdfIn PDF document text
    • https://gangnampools.com/contents/files/zemanos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=icse+class+5+maths+book+pdf+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_off0000bd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD75 11096 bytes
SHA-256: 6d6a99590a39a60895dececef46ad413feee0f593895df87fd2612245ec65002
font_01_sfnt_off0000d717.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD717 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF29 16884 bytes
SHA-256: 06ebfbf737cdb272ea4ea028af54ab6e936edbdc69551a7446b5152f1f86de86