Malicious PDF — malware analysis report

Static analysis result for SHA-256 adce7062c4360342…

MALICIOUS

PDF

70.4 KB Created: 2021-10-01 00:54:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e57b55274e1046728ef56f1d0abf8607 SHA-1: e7a98c4a9cbf8d1e5b4511a8a836e873c8a72a0a SHA-256: adce7062c4360342afa45f6c5d535ebe1003b978424222ac711e1bf4782d1c95
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads and disposable domains. The primary attack pattern involves luring users to these external sites, likely for phishing or further malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://vgk.tw/upfile/files/2021/10/01/23140602527.pdf In PDF document text
    • http://chipgene.com/image/files/20210930_090050.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613125da7f1d7---16053332543.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/nimabasuve.pdfIn PDF document text
    • http://sanjarbek.uz/userfiles/file/firom.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16140ee0eeabf7---rukidoxijejebus.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/58639864879.pdfIn PDF document text
    • https://resonanceacteurs.nl/userfiles/file/vedololinagalasazulumexos.pdfIn PDF document text
    • http://pietrek.com/MARCUS/files/file/39918130248.pdfIn PDF document text
    • http://ellissi.org/userfiles/files/70495956113.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-28/20210928011829471131.pdfIn PDF document text
    • http://ptk-tent.ru/userfiles/file/lowiwifawe.pdfIn PDF document text
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/dilakabogobev.pdfIn PDF document text
    • https://vico-real-estate.com/ckfinder/userfiles/files/23159299367.pdfIn PDF document text
    • http://studiocinti.eu/userfiles/files/rizat.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/moxefimoxadilexarotap.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/33772110466.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/foruxuzilu.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1614891d795cf8---73998484582.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/94904306172.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109042227147155.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=sylvan+barnet+writing+about+art+pdfPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147b94ee039e---72393104788.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_off0000af8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC79C 17000 bytes
SHA-256: 4c41df5be23b4c3bac13f13bbe71c3d527c4d15299147c4db5ecef19b0a135ce
font_02_sfnt_off0000f2b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2B7 11088 bytes
SHA-256: a251571f64f60bff0dd363baf82c25b78e59aaee63cbb5c6059bd9dd704d3516