Malicious PDF — malware analysis report

Static analysis result for SHA-256 92925c15d82d18e1…

MALICIOUS

PDF

66.5 KB Created: 2021-09-12 03:13:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fc68c0cb1fe1725bcba9abe48c564f61 SHA-1: d433570696505d2c11da6befde40bc31205b287f SHA-256: 92925c15d82d18e14a9828d1d6ffe9d2b45b6e2e832f197408c89cb9efc43b37
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://tranthachcaodanang.com/uploads/image/files/47831791697.pdf In PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/57555110643.pdfIn PDF document text
    • http://vuason.vn/upload/files/lagojud.pdfIn PDF document text
    • http://eiak.org/upload/editor/files/83361659039.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/46316050585.pdfIn PDF document text
    • http://evolutionchonburi.com/userfiles/files/kanejiwimatel.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16135eb4837226---dofejab.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/73853041059.pdfIn PDF document text
    • https://iagclaims.endataclaims.com/ModCoreFilesUploaded/file/81214315186.pdfIn PDF document text
    • http://salon-urody-bellis.pl/images/file/3833987074.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/94091574881.pdfIn PDF document text
    • http://hysansam.com/fckeditor/userfiles/image/zutimugupava.pdfIn PDF document text
    • https://verandapattaya.com/userfiles/files/21785407431.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa2b33018a---6933702754.pdfIn PDF document text
    • http://iscyber.com/userfiles/files/34846651122.pdfIn PDF document text
    • https://transdeliveris.lt/userfiles/file/vivavulu.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138e9b7a1ecc---moziwizexidobinuzidavoj.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///2021091284327_674288257.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=find+the+first+partial+derivatives+ofPDF 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_off0000a9ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA9AB 14104 bytes
SHA-256: 7c5b755ec6e8cd489d18b58d037cc7b3a0552b2d25fdfe46ca068e9e69265146
font_01_sfnt_off0000cc8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e4a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A3 10636 bytes
SHA-256: 8f0ac47b27aac9696a13b7163c4c48c746a87830407bf85d9dec76720c9dcea9