Malicious PDF — malware analysis report

Static analysis result for SHA-256 de44879b4b55c775…

MALICIOUS

PDF

74.5 KB Created: 2021-09-13 07:43:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 71c228f266761f49705806ad12d90ef3 SHA-1: 8059478a95da087463c2aea19cf7b3253235dfa5 SHA-256: de44879b4b55c775237a6e49f49efc5337b2fda19c6b035bffe6dbfddbd7b6ed
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains a large number of embedded URLs, many of which point to disposable domains or are used in a link farm configuration. The ML classifier strongly indicated maliciousness, and the presence of numerous external URIs suggests an attempt to redirect the user to potentially malicious content or phishing sites. No scripts were extracted, but the PDF structure itself is used to host and distribute links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 4

  • 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://cructi.ru/uplcv?utm_term=windows+7+clean+iso
    • https://iword.de/userfiles/file/24081685565.pdf
    • http://fecoil.com/userfiles/file/2463792411.pdf
    • http://zaun-produzent.de/userfiles/file/22692501035.pdf
    • http://dexgerm.com/data/file/userfiles/files/kuwunetubebalarekowolep.pdf
    • http://vitanova-cattery.com/upload/file/jolavadug.pdf
    • http://wmsone.com/eimages/file/penowuvu.pdf
    • http://asqcert.net/files/files/75583427742.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/161322ea0742c3---48104839384.pdf
    • https://99shayari.in/userfiles/files/rimixu.pdf
    • https://www.comperat-89.fr/ckfinder/userfiles/files/kuveruva.pdf
    • http://dalhousieretreat.com/cote_dor_import/admin/ckfinder/userfiles/files/21315990016.pdf
    • https://nls.vn/upload/files/virivekiraxowufela.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613955e79ab63---65730134312.pdf
    • http://phone-server.com/userfiles/file/82673105029.pdf
    • http://wxhsbl.com/ckfinder/userfiles/files/20210906_084411.pdf
    • https://majubesar.org/contents/files/zupubozupupodewerutedediz.pdf
    • http://fred-robin.com/ckfinder/userfiles/files/92192876849.pdf
    • https://morganmethod.com/ci/userfiles/files/bikomebogimufevad.pdf
    • http://www.sanjuktabanerjee.com/fckimages/file/53057179757.pdf
    • https://lajovisena.com/gallery/file/suzusuturopanifilonolu.pdf
    • https://riosemarescentrodemergulho.com/ckfinder/files/rewurofek.pdf
    • http://hyundai-dongdo.vn/images/files/74936653113.pdf
    • http://m-s-g.ru/userfiles/files/wuwalatowejijovuzusa.pdf
    • http://alessandrotria.altervista.org/areap/ckfinder/userfiles/files/bawenuxeluxenol.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c324.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0xC324 16792 bytes
font_01_sfnt_off0000db3b.bin
43d32664ebd84934824cf967816e6c5b84d8aff01f62948ff5ca3677ac4bd5ab		 pdf-font-stream PDF embedded font (sfnt) at offset 0xDB3B 10296 bytes
font_02_sfnt_off0000f29b.bin
79a62060ddae493cca10c260be6a202d293d6591616214ef645853010accdc35		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF29B 16336 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.