Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c1094925a28202f…

MALICIOUS

PDF

73.8 KB Created: 2021-09-19 14:14:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6e72bf3e28656f1c8dfef09479316c22 SHA-1: b93a1344e1ce4bcd796857ebec8076fe1bcd42c7 SHA-256: 8c1094925a28202f26fa4eb470584fc24001082e42e18af0984fb782e4b11485
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised CMS upload storage, suggesting a link farm or phishing lure. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135ba52778c4---keben.pdf In PDF document text
    • http://guanzhuli.com/userfiles/file/garedom.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136bb883edc6---37843851989.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/15420047083.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/hg2h88s5jm5o7kj8fpqmjg7srq/kakerera.pdfIn PDF document text
    • http://hichipper.com/hichipper/uploadfile/file/2021091819131373499.pdfIn PDF document text
    • http://xn--lv0az70cxar.tw/uploads/files/202109131503069724.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/miripijixebosuk.pdfIn PDF document text
    • http://bordahusfeldolgozo.hu/editor_up/69953222686.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/pilawivifesapipikabub.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/levukari.pdfIn PDF document text
    • http://szolnokepul.hu/userfiles/file/64268232715.pdfIn PDF document text
    • https://ptogel1.com/contents/files/zesaninotejegabuxesinezar.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/22646925442.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/jaritolafuluvasarus.pdfIn PDF document text
    • https://consultemergingmarkets.cubsindia.com/files/3329334518.pdfIn PDF document text
    • http://gsxr.hu/userfiles/file/86793168286.pdfIn PDF document text
    • http://avtrak.ru/ckfinder/userfiles/files/nolebudabajabeni.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b06678c188---gipalogofexuwifoxamup.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/13018254079.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/vinozezaseroja.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/161463a8cc2442---magulojomanogakex.pdfIn PDF document text
    • http://area100impianti.it/userfiles/files/40435702401.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=saving+normal+pdfPDF 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_off0000bdac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDAC 17124 bytes
SHA-256: 7edbde59bbd0a11e25231f53a46c99b624b09f19b44aa4ed3fc017bfe02690a8
font_01_sfnt_off0000e9eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EB 10584 bytes
SHA-256: 1eb95a9c72f4abb08596bfc411b4ce2cff66dc21c4156eadc856919301b82de5
font_02_sfnt_off000101cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1