Malicious PDF — malware analysis report

Static analysis result for SHA-256 791c5048eaf206c9…

MALICIOUS

PDF

86.1 KB Created: 2021-07-02 04:33:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 373d3ffc3f052fe9e9a90323d89933c0 SHA-1: ad2d288b7b8e64a5ccc7e4f6cfdf536fcea017bb SHA-256: 791c5048eaf206c910d5cf24b607349b1c60e039f676fc957cf924b61f9cab04
164 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://akcjonariusz.com/UserFiles/file/diwamamodufebuxor.pdf In PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c97ad5a0ec6---95644943120.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a8c1ae96638---12304992804.pdfIn PDF document text
    • http://sevinctekstil.com/resimler/files/kadinofafigidenono.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073b8c616a66---zuxor.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c22a6b865---90571239744.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/53523629927.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/e158c62e591325cfadcbf9fd90564a97/zokejabos.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/28589162356.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2b94f29b28---92065153512.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/79485779618.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/f40ff441ecc1f2d8b704ed4010525e32/xikok.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/4a6994bf84927f4b174596c41efb9e6f/xoruka.pdfIn PDF document text
    • http://klhl.com/userfiles/file/pizatama.pdfIn PDF document text
    • http://tradeweb.es/userfiles/file/23820870216.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb8fc42ade---zitewoliruwumumukovexozu.pdfIn PDF document text
    • http://iehyun.com/editorupload/file/69810333098.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609243114737e---15316703329.pdfIn PDF document text
    • https://mk-promotions.com/ckfinder/userfiles/files/filekavibara.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b4bfc89c1e6---88448630352.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e53e2439a---lipapusof.pdfIn PDF document text
    • http://ehoron21.mn/uploads/files/vedeze.pdfIn PDF document text
    • http://menloathertonhigh1980.com/clients/6/6f/6f83464fe0b13873896cace574d4baa5/File/dezezojuxak.pdfIn PDF document text
    • https://andrejc.si/files/file/60304498150.pdfIn PDF document text
    • http://meta-min.com/files/fubomuvoziga.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608612a71678c---19658818468.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=new+simplified+chemistry+class+9+icse+solutionsPDF 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_off0000e85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE85A 18016 bytes
SHA-256: 3a5a17396a3735b6e780639b30c122f4627478053947c126e9a80fb3f10e905d
font_01_sfnt_off0001180b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1180B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013022.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13022 11332 bytes
SHA-256: 19d0b3263cbfbd7f5267efc776138ea81fd2f5c3002d6ea5421387795bfb3634