Malicious PDF — malware analysis report

Static analysis result for SHA-256 4641b0b6d4f7d15a…

MALICIOUS

PDF

79.2 KB Created: 2021-09-19 00:46:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ac86da98313bd95b5ce85fbabda173e7 SHA-1: a51a74c33c0a21777eb7ba3d73d417cec60c95b0 SHA-256: 4641b0b6d4f7d15a9661e30341bdb9a755d54563db8aaf7e2db0ef7da3c94c1b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to external websites, with some identified as link farms on disposable or compromised hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to direct users to phishing or malware-hosting sites. The primary attack pattern observed is the use of a link farm within a PDF document to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://dolphinkorea.com/files/files/26858403943.pdf In PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/92451749764.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/lizudifaxovelixolu.pdfIn PDF document text
    • https://vozilasavozacem.rs/files/zerefotitibavopawame.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/moxapofofuju.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134e1a5a68c6---12855403717.pdfIn PDF document text
    • http://starma.pl/files/file/42630201671.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a76408d778---32121426567.pdfIn PDF document text
    • https://nationalshield-uae.com/userfiles/files/94547851070.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/jitobilak.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/ef215bb2f94f1bbfd2833cd52b12e5cb/72969752026.pdfIn PDF document text
    • http://wacommerce.net/home/integrity/public_html/ckfinder/userfiles/files/zovusozexatiwote.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/78160744082.pdfIn PDF document text
    • https://www.vasutaszeneiskola.hu/ckfinder/userfiles/files/74885976778.pdfIn PDF document text
    • http://xn--12cfu9bc1efac9a9azfdsb7b9d1f0j.net/ckfinder/userfiles/files/mofiniled.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/51600415066.pdfIn PDF document text
    • https://hefcom-hydraulics.com/ckfinder/userfiles/files/fukafopaxipoz.pdfIn PDF document text
    • http://gustosandvic.com/ckfinder/userfiles/files/lojutitusi.pdfIn PDF document text
    • https://www.karelo.com/uploads/File/ruxuzopile.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/kogavu.pdfIn PDF document text
    • https://phucatgarment.com.vn/ckfinder/userfiles/files/fofazoxopukariwu.pdfIn PDF document text
    • https://forssh.com/userfiles/file/59228400535.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/14563699818.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+share+videos+from+android+to+iphonePDF 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_off0000cffb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFFB 18264 bytes
SHA-256: 96b48041adf283aa422e4118c5ffadc130df51a6eebbe862798cf0c4c2349cc0
font_01_sfnt_off0000fe3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011653.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11653 10860 bytes
SHA-256: 161b5af40642d702328945d8247a9a7e0841f641282ce9a5b5eab7b5e7e1bd1c