Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f41dda664b1289f…

MALICIOUS

PDF

76.9 KB Created: 2021-09-03 15:54:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: fe0ff5b4c9d124013efbe4f1055566df SHA-1: 725000c4ab02b0a89fbaa208c051e1e6bcc23531 SHA-256: 3f41dda664b1289f0f8b0590e523d6eef8418366864b5680ba97ba61d1c5a4cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were directly extracted, the PDF structure and URL patterns suggest it's designed to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/bvgvstmbtnj2m7kh086segini3/tadebanizexamulagisobi.pdf In PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/29977541062.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/40110323784.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/falezogelijowisafujotu.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/960e1f60d1cf42f51c10daf3a69607e6/6796257120.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/pojurulovejobamaw.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/gizumaz.pdfIn PDF document text
    • https://iguanapools.com.au/wp-content/plugins/super-forms/uploads/php/files/sdvc0fr52tjk79bol581bggvlb/nalemasasibo.pdfIn PDF document text
    • https://obermeyer-modemarkt.de/upload/file/zuwarojesarimazeboz.pdfIn PDF document text
    • https://airbays.com/userfiles/file/legutizokafomukug.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/46968882175.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/dixemepusum.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/1274081386.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/bijola.pdfIn PDF document text
    • https://fivetc.net/uploads/files/88516810919.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/89527252877.pdfIn PDF document text
    • https://auto826.com/uploads/files/3425283436.pdfIn PDF document text
    • https://drsubhashawale.com/ckfinder/userfiles/files/37775524351.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/j1qtp351biv84921n458mc81aj/mizazitotukogiliv.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bd655a087f---78401885440.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/fotavunib.pdfIn PDF document text
    • http://dongkoo.com/uploads/editor/files/duxerobelujer.pdfIn PDF document text
    • https://exam10.menapoint.com/app/webroot/upload/files/51885624192.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/wesagunag.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/0129f098df328e5e2005826c6a6289d6/mujunisokusofixef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=omron+scale+bf511+manualPDF 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_off0000c424.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC424 10756 bytes
SHA-256: 3f415e35295496125be3165087bd45b915002bf440f690e74ba31c7745416e93
font_01_sfnt_off0000dcfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCFD 18908 bytes
SHA-256: b989299c2ced5ecadb762254b624f47a8876a6cafe67fe5ce4b5993b59c49f62
font_02_sfnt_off00010dc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1