Malicious PDF — malware analysis report

Static analysis result for SHA-256 66b37daea8d9da6f…

MALICIOUS

PDF

83.0 KB Created: 2021-09-15 23:52:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1cca6f51b4ae672a8d7a500faca7cfdf SHA-1: 882459fa838dbbfb25699c213c77ca478a9413f8 SHA-256: 66b37daea8d9da6fc5cc2724f69feb7e1de91283464aad6a07263ebf0ef8b741
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm used for phishing or malware distribution. The PDF's structure and embedded links indicate it's intended to redirect users to malicious sites, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://watosaphotography.com/app/webroot/userfiles/files/20210903_185323.pdf In PDF document text
    • http://divorcefinance.nl/uploads/file/76258410652.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/17793130756.pdfIn PDF document text
    • http://depcip.com/app/views/panel/ckfinder/userfiles/files/mexivibe.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138deb51ee90---fizevilunudodusude.pdfIn PDF document text
    • https://eletvital.hu/uploads/files/davemosurox.pdfIn PDF document text
    • http://parikshitconstruction.com/uploads/73667254615.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/70256087788.pdfIn PDF document text
    • http://akbarestate.com/survey/userfiles/files/98589844658.pdfIn PDF document text
    • http://dietetyka-24.pl/images/files/78321373607.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/1508838802613210c7b71d3.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369ca91436f---lolavasuvifadujexux.pdfIn PDF document text
    • http://phonphangschool.com/upload/files/waleba.pdfIn PDF document text
    • http://mertcelikkapi.com/userfiles/file/23625318154.pdfIn PDF document text
    • http://criminisiepartners.it/userfiles/files/24074284131.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613730404a9e5---zadujuvogodenupolovo.pdfIn PDF document text
    • https://propactionvehiclesuk.tv/userfiles/files/kurusejivexolegeto.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161405c2d415de---3281908598.pdfIn PDF document text
    • http://heryeryesil.com/resimlerfiles/xenosipizatuvuxigidesom.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/xafitetunewizasowajiwonog.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/68689304929.pdfIn PDF document text
    • https://acconpriti.com/ckfinder/userfiles/files/tegekul.pdfIn PDF document text
    • http://lavalnerina.com/userfiles/file/zolow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=cant+send+photos+to+androidPDF 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_off0000e362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE362 16496 bytes
SHA-256: 80250e5ec87573cf3247e7b4cea9c57373aaa8cdb67233aba7b2d40dfd480086
font_01_sfnt_off00010e39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E39 10476 bytes
SHA-256: 3c2196ae0f5f7ed603f79574481716460ab4c3577004f771e99e1e02e79b49cb
font_02_sfnt_off000125f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1