Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ff67837987845e7…

MALICIOUS

PDF

68.6 KB Created: 2021-09-28 20:49:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 9052c75b2dcc0405aa0adbec5eaa0470 SHA-1: 77a049c490d0a2aa82ae527cffc02c2dd0339f0a SHA-256: 7ff67837987845e741531277312027fa6b9b72e7cf337c0a70782c9140f469b3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV, indicating it is likely a phishing or malware distribution lure. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it is designed to redirect users to malicious content. The presence of these links and the overall structure point towards an attempt to exploit users via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://medvor.ru/uplcv?utm_term=how+to+record+mp4+video+on+android PDF link annotation
    • http://truhlarstvisollner.cz/data/file/28414288929.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/lusawujikupabuzaf.pdfIn PDF document text
    • https://iwanbim.com/userfiles/files/tedujixobatu.pdfIn PDF document text
    • http://yourtruck.be/upload/ckeditor/file/jixizafidulumaxugoganexap.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/92078707396.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbb94e3266---poxolegirufitiwuvafede.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/47676455579.pdfIn PDF document text
    • http://theonejsc.com/userfiles/file/fimojerapoxudefokije.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c364ba71af---23213253093.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210920_95DB7C91DB6E5DDF.pdfIn PDF document text
    • https://tonwen.org/userfiles/file/67632777298.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/49813115972.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/cbdc18d2c4459939052b012822f7679a/42881069496.pdfIn PDF document text
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fafukeji.pdfIn PDF document text
    • http://furniture83.com/upload/files/29193051131.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146ca3d7af95---wuwolugabuzinarisinotor.pdfIn PDF document text
    • http://perfect-gallery.com/userfiles/file/67702853811.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/21134958227.pdfIn PDF document text
    • http://www.miyadenthai.com/image/upload/File/55166618065.pdfIn PDF document text
    • http://liweisteel.co.th/ckfinder/userfiles/files/38005355232.pdfIn PDF document text
    • http://gardens-spa.com/user_pict/file/81913554.pdfIn PDF document text
    • http://a-aqua.fr/ressource/site-image/files/97751814366.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_off0000ad57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD57 10680 bytes
SHA-256: 3c15b3035ca68102058676ecf0879c1958e4693471cff5836aa73bd86a71a3a0
font_01_sfnt_off0000c5d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ddeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEB 14852 bytes
SHA-256: 6af9aa7fadf7a3732cf272134528b159095566b4a1619be4fc5f82dcf3b7fcea