Malicious PDF — malware analysis report

Static analysis result for SHA-256 4936fb9ee927bb68…

MALICIOUS

PDF

77.0 KB Created: 2021-09-04 12:29:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c2fa26689470e4dfadaa2d0e650a7e5f SHA-1: 42c22715e26617ea0e39d6b55a49825dcc5cc5eb SHA-256: 4936fb9ee927bb689946504a702da7b514ba5a2f0401084da16ae82abcb7ca69
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the heuristic firings clearly indicate a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://adsbudget.net/userfiles/file/22959738339.pdf In PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/5rppn9rvgso2dlggu8skdtvnt7/86134944101.pdfIn PDF document text
    • http://doyen.cc/images/upload/File/zanapenosebakigewapot.pdfIn PDF document text
    • http://www.dean-cpa.com/files/adminpic/file/satelupazozozusupupafev.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///98102724387.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/wesofakofiviju.pdfIn PDF document text
    • http://szpk.hu/_user/file/68166506205.pdfIn PDF document text
    • http://suliaox.com/v15/Upload/file/20217311059236845.pdfIn PDF document text
    • http://ychnjl.net/userfiles/files/93096609965.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d62d856a0---99402503519.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f98fef66cef---kedafasifujogilex.pdfIn PDF document text
    • https://papersacksfactory.ae/images/bulk_images/files/dudonetavezavigefebet.pdfIn PDF document text
    • http://pressvaluation.net/userfiles/file/kowilafomorek.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/a00b0682f9bee165328c2cde97ab28f6/xixulepo.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/resoguzimafufowof.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa271561272---xenuwinunesalavutowexam.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607434bc5cbfb---3137912241.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/ce2ie6kpgsvkmtnneo0ui46e6o/38532159452.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086573c0c1d7---41257132467.pdfIn PDF document text
    • http://nfrostov.ru/upload/files/jurokuzexa.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5b4ed91f3---rixefev.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/ramomonabapadi.pdfIn PDF document text
    • http://klimagra.pl/images/wysiwyg_img/file/1446605365.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088ef9bb101d---lozefinejisul.pdfIn PDF document text
    • https://avenue102.com/uploads/file/2606519535.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=90+day+workout+plan+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_off0000c896.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC896 17588 bytes
SHA-256: 257c028592cf781d2ab68df56984807a3781ea7ff0b875a551cd04cc1b448067
font_01_sfnt_off0000f614.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF614 10684 bytes
SHA-256: 4bbb7d15ff3ebc684f6e0e3d095fc142820fb63bf949030be4b74df2040ec29c
font_02_sfnt_off00010ebb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1