Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac764bc82557ce83…

MALICIOUS

PDF

86.2 KB Created: 2021-09-19 05:30:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0251fbea0c637cfb20b62f037c02f452 SHA-1: ce8f13b908667dc70c3d5d629a4932e488d16c6b SHA-256: ac764bc82557ce83ea6413cc9b75998531f8e01ee119840b2969de7035979aac
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, but the overall structure and heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://jobcred.com/rk/jobcred/uploads/image/file/bekuwonuzofe.pdf In PDF document text
    • http://edituj.cz/res/file/44334279623.pdfIn PDF document text
    • http://riviera.az/userfiles/file/91989021980.pdfIn PDF document text
    • http://kingswaytyres.com/project/kingsway/uploads/file/33572576385.pdfIn PDF document text
    • https://4of100churchstreet.com/assets/media/files/59956000080.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614213745a6e0---dijivowukovul.pdfIn PDF document text
    • https://artesapanaderia.xyz/aym_image/files/3621697938.pdfIn PDF document text
    • https://santevita-bg.com/ckfinder/userfiles/files/muxekokunilisejijebalonuk.pdfIn PDF document text
    • http://timebymtm.com/upload/files/84143238286.pdfIn PDF document text
    • https://hse.tw/upload/file/ralimobedasefitidadi.pdfIn PDF document text
    • http://quick-thailand.com/images/uploads/file/65605346397.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/53041504146.pdfIn PDF document text
    • http://poiskvod.ru/images/file/78976448122.pdfIn PDF document text
    • http://music-saikung.com/ckfinder/userfiles/files/lulisilobapibexagegeg.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613af32ea991d---10682823626.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614218b95d6f0---riwotutimipozolotekaxa.pdfIn PDF document text
    • http://es-manzokudou.com/yamituki-n/uploads/files/ruripoxaluki.pdfIn PDF document text
    • https://ducthai.vn/userfiles/file/dugom.pdfIn PDF document text
    • http://delfosventures.com/userfiles/files/18686058876.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/luzejavaxebelujukoxore.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/20847246476.pdfIn PDF document text
    • https://ahl2005.com/ckfinder/userfiles/files/8864860660.pdfIn PDF document text
    • https://ijacr.net/assets_admin/ckfinder/core/connector/php/uploads/files/8049358875.pdfIn PDF document text
    • http://gidaero.com/upload/fckeditor/file/xonekoduge.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/8616164530.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/64949904112.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=magnet+torrent+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_off0000e4ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4EF 20960 bytes
SHA-256: c9cdc9f6822463543b4b9f68c692ee2404f4225b8f96ffa4d9bbc66379e41e7c
font_01_sfnt_off00011c29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C29 10208 bytes
SHA-256: c3dcdfde5e89a71c045f2d54fe7525dcd3e44268f8e71d9f6bef98a7a742b1a0
font_02_sfnt_off00013330.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13330 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1