Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5cae0c8f24583f8…

MALICIOUS

PDF

68.3 KB Created: 2021-10-28 00:19:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 12fb785f1500e7cca46d8d3fe2b74e29 SHA-1: 489acc2ee121967169f14d13212abf053fab26fa SHA-256: d5cae0c8f24583f827d00f5a256286ff9196e462bf40611422ea942b76b8ddfb
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to various domains, many of which are hosted on disposable or compromised CMS upload storage. The ML classifier strongly indicated maliciousness, and the presence of multiple link farm heuristics suggests an attempt to obscure the true destination or distribute malicious links across many domains. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9851

Heuristics 5

  • 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://webrobogo.hu/kepek/xikewi.pdf In PDF document text
    • https://sapsda.com/SapmaUserfiles/file/64377749074.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/xerukirizogidojuxe.pdfIn PDF document text
    • https://nycsmindia.org/ckfinder/userfiles/files/tagapa.pdfIn PDF document text
    • http://energywork.pl/userfiles/file/mamamevusapum.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/vipizijobopadupikedad.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/80317700648.pdfIn PDF document text
    • http://americasbestwingspa.iorderfoods.com/uploads/files/gajabujikawukotosepiz.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612fea0c30fc2---7677772361.pdfIn PDF document text
    • https://petribax.nl/userfiles/file/59107211565.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/ffe8bff2c4ca1c82992c10cd735ad183/59484968845.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/89756305695.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/78088322636.pdfIn PDF document text
    • http://orourkelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sebezopiwu.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/8f76ab441554cacc56c31f263ab88501/dekiw.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/purusa.pdfIn PDF document text
    • http://bojovesporty.cz/userfiles/file/tomaliji.pdfIn PDF document text
    • http://xn--brneneskontor-landsforening-b0c.dk/userfiles/file/nunojafesatabadiluwar.pdfIn PDF document text
    • https://ozmutludokum.com/userfiles/file/dexasoweguvukijejuwonulag.pdfIn PDF document text
    • http://studioferrato.it/userfiles/files/53768785698.pdfIn PDF document text
    • http://tainghe.vn/userfiles/file/kulinizatazilifomudep.pdfIn PDF document text
    • https://amt-alarmy.pl/userfiles/file/74400694019.pdfIn PDF document text
    • http://honghuibio.com/d/files/45568104499.pdfIn PDF document text
    • http://embody.box8websites.com/ckfinder/userfiles/files/21738597517.pdfIn PDF document text
    • https://possamaiferramenta.it/uploads/file/29276249525.pdfIn PDF document text
    • http://airelimpio.mx/img/editor/file/sopelireref.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/6Zflnl449io/uplcv?utm_term=having+a+dirty+mindPDF 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_off0000b1ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1AE 10296 bytes
SHA-256: b40fc092b5c79ecd99589692be84b97e3d99037700c2d2c99d5438ec79e28dad
font_01_sfnt_off0000c88a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC88A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e09c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE09C 14376 bytes
SHA-256: ba9dad9534f6561a29a92029dc021caa477e476e5a131e68afd24e700d20e14b