Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2b847a326afde3c…

MALICIOUS

PDF

82.0 KB Created: 2021-09-13 13:50:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f96088349d65263353b668b39b90fe44 SHA-1: 1a393c265461d8447b6ba53e922fea9a3313a7f8 SHA-256: a2b847a326afde3ccb50a453795caa6fb35055ac621aa2c32656272febb9977a
74 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the malicious intent of directing users to potentially harmful sites. The presence of embedded JavaScript suggests an attempt to execute malicious code or further obfuscate the redirection process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://stainless-faucet.com/uploads/htmlupload/files/pegodadilobafidafuz.pdf In PDF document text
    • https://nguoixunghekiev.vn/userfiles/file/zufedubuludisa.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pikufope.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/devilaka.pdfIn PDF document text
    • http://agro-norwa.pl/userfiles/file/moduvubotusipowoximo.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/62453276254.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd6253827b---jekaxuxemosekunegekotuso.pdfIn PDF document text
    • http://syntrend.critical.tw/upload/files/14398627999.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/sezatusevebuwukakatawila.pdfIn PDF document text
    • http://sun-marche.com/app/webroot/js/ckfinder/userfiles/files/49376839678.pdfIn PDF document text
    • http://speckrepej.com/upload/file/sitililoxizopunilexi.pdfIn PDF document text
    • http://unibox.lv/files/text/42133513818.pdfIn PDF document text
    • https://dammesliepas.lv/ckfinder/userfiles/files/bedugegezipexeteregibexub.pdfIn PDF document text
    • https://sofahatinh.com/upload/files/96692386415.pdfIn PDF document text
    • https://ka-base.no/images_content/file/peluzikodav.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/26983387839.pdfIn PDF document text
    • http://mdfgiare.com/upload/files/rapepovurezivev.pdfIn PDF document text
    • https://www.thaiahpa.com/flash/files/79824546223.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__61354500A0400.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/zabinekemegokuwikasa.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/54637682619.pdfIn PDF document text
    • https://euronuts2009.ge/files/files/16982466889.pdfIn PDF document text
    • http://factblogs.com/uploaded_files/userfiles/files/sejaluzoku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+download+videos+using+phoenix+browserPDF 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_off0000da91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA91 11156 bytes
SHA-256: 146f41494974241328d59086db5478faeb7770e420b52b1522d6d68b647eb993
font_01_sfnt_off0000f423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF423 17796 bytes
SHA-256: 5ce70200ca76e184f6ed9622e12f2a48279f3f3bd919fe3198559c283964b0a6
font_02_sfnt_off000121da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1