Malicious PDF — malware analysis report

Static analysis result for SHA-256 d163149f94a654a2…

MALICIOUS

PDF

74.7 KB Created: 2021-09-20 06:25:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8e31a88c0c4395ea57bf0569e2529d2d SHA-1: 7c38aaab5163bf08f7c5ebd5282c9ead4ec3bc54 SHA-256: d163149f94a654a249842f497193bdb9df539cc5e20b1a7704832af70c5353ec
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload storage, indicating a link farm designed to lure users to external sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://sutipatika.hu/userfiles/files/89224151895.pdf In PDF document text
    • https://steammining.com/userfiles/file/31112589925.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/23269128939.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f5e6ceaf1---rizunenofep.pdfIn PDF document text
    • https://nexapos.com/upload/files/47903763624.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/baxulowofeputakasigujigej.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613c59888167a---10729358146.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/89767714331.pdfIn PDF document text
    • https://greenboo.vn/uploads/files/fedonajuradopelemidubofo.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614166254f42c---bisubege.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/25631208780.pdfIn PDF document text
    • http://ig-einheitsloks.de/medien/file/daviguredaru.pdfIn PDF document text
    • https://lnpro.in/ckfinder/userfiles/files/dorofabufesato.pdfIn PDF document text
    • https://adtw1.com/ckfinder/userfiles/files/9854913267.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/81083168268.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/64836852164.pdfIn PDF document text
    • https://endobible.com/userfiles/file/ponosil.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/ab10c083854c4b4cac6dbe5bc882ea07/72791424428.pdfIn PDF document text
    • http://rigosarchitects.gr/userfiles/file/lozegelimodo.pdfIn PDF document text
    • http://kelvista.lt/images/files/23254204860.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/megur.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140157984a54---xejabexesuzemofelifajofa.pdfIn PDF document text
    • http://efeotokiralama.com/Upload/file/ravugesi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=download+tv+app+repo+apkPDF 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_off0000c3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBC5 10368 bytes
SHA-256: cdf2cc7a5d29dcee44a1cd68bd85adf0ff325ab59faf49286c90a1233916867f
font_02_sfnt_off0000f35d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35D 16308 bytes
SHA-256: 0b3fb8bd87d3f37256c7857bfc3b4e9281d38514f2c19ae8d13877c08539be73