Malicious PDF — malware analysis report

Static analysis result for SHA-256 65d45167a9e9384b…

MALICIOUS

PDF

79.1 KB Created: 2021-09-13 15:50:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 040ed513ea3874ede9da43f9068ca7dd SHA-1: c3b7e2528cb9539b8557bb2fdfcafd151982abae SHA-256: 65d45167a9e9384bffa9ae65ef9c7eedaa61550497fccca341ca2b86e9404e4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload storage, indicative of a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the URL patterns and heuristic firings are sufficient to infer a malicious link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://accessprecision.com/userfiles/file/gufejasonol.pdf In PDF document text
    • https://angkaganjil.com/contents/files/72270376255.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/8217199517.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/jawene.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/59373114276.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/novavi.pdfIn PDF document text
    • http://gzmingjun.com/uploadfile/files/20210908_024703.pdfIn PDF document text
    • https://cargobull.cz/res/file/kunod.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/dasemomazetetit.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161351fd84e369---4934117200.pdfIn PDF document text
    • http://poliinc.com/upload/files/71670623280.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161396b0c4e26f---fukasenera.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/09-04-15-32-36-33.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/hj7lc6ns1hncdv3k134s92fe6h/75117327739.pdfIn PDF document text
    • http://syekp.gr/sites/default/files/file/53293061383.pdfIn PDF document text
    • http://gzbaosui.com/uploadfile/files/labijud.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/boxebivufewaf.pdfIn PDF document text
    • http://trubaopt.ru/content/file/wipuxomazunovupomeji.pdfIn PDF document text
    • http://debschoen.com/userfiles/file/turinunonutokixox.pdfIn PDF document text
    • https://superchills.com/userfiles/file/dumebun.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xokibodumanikoxadivavo.pdfIn PDF document text
    • https://erdenet.mn/userfiles/file/rijudusabadoxatujapalu.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/fe35a085537ebda8f4911badf06e259b/simaduvugise.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/vimetipoke.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=hide+vault+appPDF 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_off0000d07f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD07F 18332 bytes
SHA-256: 580ad19d052a5249e989cc4699997e21a81736e569d6958e7fa7fd1e26121593
font_01_sfnt_off0001003e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1003E 10052 bytes
SHA-256: 34b1017bfd3b7cff560777ecf504974bd2be8c85c2cb7551e76cbcbd65918719
font_02_sfnt_off000116aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1