Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4242edc5d030e16…

MALICIOUS

PDF

73.7 KB Created: 2021-09-24 11:38:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 961852b5a7e178832d05f45f3efbfacd SHA-1: f50197dd5cf89e3597229d84648a50918779642b SHA-256: a4242edc5d030e160fdbfabbe7cf24f2af2d47b8e4c71087ad5240be0c5c10ca
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://stephan-kratt.de/data/reiterhof/userfiles/file/72554795217.pdf In PDF document text
    • http://fst-uinsu.net/userfiles/files/25883222525.pdfIn PDF document text
    • http://xy-interior.com/uploads/files/202109120323395071.pdfIn PDF document text
    • http://michael-dhom.com/webseiten/file/14563645421.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16136a2a741086---43877289501.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c630ff2924---84123223331.pdfIn PDF document text
    • http://celeb.huh.hu/UserFiles/File/12592231195.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/lulujot.pdfIn PDF document text
    • http://zlzljc.com/uploadfile/file///2021091100514772.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/535110949.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/vexuvenirawebe.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/79669087080.pdfIn PDF document text
    • https://ibexquimica.com.br/ckfinder/userfiles/files/29330243534.pdfIn PDF document text
    • https://marblobathware.com/app/webroot/img/files/nufaberulegem.pdfIn PDF document text
    • http://gaytonfa.com/upload/files/43283587552.pdfIn PDF document text
    • http://dtpokebar.com/uploads/files/tarovofu.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/fokaneledifek.pdfIn PDF document text
    • http://www.moyekolodin.com/files/wefamuwajokef.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338d2da6c21---rabedeje.pdfIn PDF document text
    • http://holland-ex.com/images/blog/file/tavebaxavapete.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/16874102160.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=which+vpn+is+best+for+thoptvPDF 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_off0000bf4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF4D 10568 bytes
SHA-256: 46fba03ef2d807330906719a229160c57b2410e7f87538e2b339483a5caf6301
font_01_sfnt_off0000d72b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD72B 16532 bytes
SHA-256: 375511df1049e166d07c8674d140ea3066c14c903a6426847aa23250a1551892
font_02_sfnt_off00010125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10125 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1