Malicious PDF — malware analysis report

Static analysis result for SHA-256 43cd03ba45af3978…

MALICIOUS

PDF

85.9 KB Created: 2021-10-18 07:37:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: afe03507249defed613cbe8944f4d6a7 SHA-1: be3d0425c3b66c118bd1e05fb69234749e354f6f SHA-256: 43cd03ba45af397893362c3179817cfdccff7361ba6c585e3c0186f4e3a122eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the structure and heuristics point to the PDF acting as a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://10kshot.com/customerinterview/ckfinder/userfiles/files/16595195041.pdf In PDF document text
    • http://tarp.longi.tw/uploadfiles/lukesu.pdfIn PDF document text
    • http://dagmare.de/userfiles/file/70254103363.pdfIn PDF document text
    • https://hattoco.vn/images/ckeditor/files/furigakizat.pdfIn PDF document text
    • http://vce34.ru/attachments/file/parobamixufu.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/vemuzidudonosisogemafo.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/gofobilexeradoje.pdfIn PDF document text
    • http://fusen-es.info/yamituki-n/uploads/files/namolijexovogi.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/dugazax.pdfIn PDF document text
    • http://heyumpnd.com/userfiles/file///68602865721.pdfIn PDF document text
    • http://vinabomi.com/uploads/userfiles/file/62689362015.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/4b43f686e11aaddde0ddcc1931c480ce/mozabujuvof.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49312751557.pdfIn PDF document text
    • http://thevisionkharj.com/userfiles/files/pumobekenakojanifaka.pdfIn PDF document text
    • http://stavclearing.ru/upload/files/tavimosarogu.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/kazijivexorizapajekuxo.pdfIn PDF document text
    • http://symbolfoods.com/files/file///72850728037.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16150a4937f498---87075165041.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/aec3d01ba07fcfbc989850cd26f6cde9/57840939489.pdfIn PDF document text
    • http://hanifeugur.com/image/files/xirerajoxugusivot.pdfIn PDF document text
    • https://comillaspostgrado.es/userfiles/file/kumixuke.pdfIn PDF document text
    • https://basisnomor.com/contents/files/nitidaf.pdfIn PDF document text
    • https://www.benkorner.nl/admin/library/ckfinder/userfiles/files/xatejumaromipe.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/RhDyTiV0TgQ/uplcv?utm_term=questions+based+on+significant+figuresPDF 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_off0000e98f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000101a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A1 18612 bytes
SHA-256: e991afdd6d8920d6b40cd71b5e24e96fcc8904903b807355094f640480462903
font_02_sfnt_off000130b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130B5 10904 bytes
SHA-256: bc90f0387fbb25c8e578ab7ed91c0d36956fb1c46846c43f3980e324eddb4162