Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dad18560dc84334…

MALICIOUS

PDF

86.8 KB Created: 2021-06-27 00:58:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: f0b2e14d75f5e22665a34866eec9b92c SHA-1: 1cb025adf3f260942f691439eacd251aae9f5eb5 SHA-256: 8dad18560dc8433432bc3a50641b3fd1f1cfc5ab0234ce5301de5e694c315566
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm on disposable hosting, further supporting this assessment. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • 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://stevis.cz/files/file/dabepis.pdf In PDF document text
    • http://www.lugashotel.com/data/editorfile/55216701765.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079d61ba2161---filibej.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/32715248408.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160875b8f083d6---fazuwonejitinam.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/82c15e3f5fad88471af926855de0eda6/67776174934.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/kinevakuwitusa.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16075ee6940872---48631509891.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/23898743ab46c65c71b36dad7d699fdf/pijanijumuzogegediget.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/v5rlscha19b8bppdp5a4g45o2l/nedubosorujus.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f2c2ab99f---xoxoxu.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ee52abb310---78008390618.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/9vpag1natneljg5nkj0g4qnff3/surekazepoxope.pdfIn PDF document text
    • http://reutlinger.pl/userfiles/file/ruwomelojapawivuwezob.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/1ca6babad291ae4d7ad287197ea27157/jaxepazerevaxujuvuda.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086aae8b0831---45431911432.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/fl9ftb6gkefq020b5podv0lu1t/36664437630.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da95462478---disagesevopuvawid.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/91116838933.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1c2538032c---75049227500.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/9034d4bbe84266af757a34381275f1cb/xizusabup.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/a39bed425920df13ed65407bc164594a/40418006491.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8a412a5c2---wenirowufikuxozumokofatob.pdfIn PDF document text
    • http://jdhs77.com/clients/58520/File/54044065514.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16078cafa7c384---kafakokibexolomogesaxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=the+finished+mystery+pdfPDF 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_off0000f231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF231 10512 bytes
SHA-256: ae757ebb6da5616a0bda4a84521503abd51303a04bbc723bf2f09393636c6565
font_01_sfnt_off000109ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121FE 16904 bytes
SHA-256: f26af6c9c72ca2cdb3b353703697e51fdc295c0160efd9e4c1d5a2a100674efe