Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e3bb5c3d6b19f65…

MALICIOUS

PDF

79.1 KB Created: 2021-09-06 12:53:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 89c65e3f7ecb8a083868be7bf41e1c77 SHA-1: b8fd6b293a107bf40572664c7d36c99a7547c747 SHA-256: 9e3bb5c3d6b19f65adb5f9adb2a62c99b32fa06269f17bff10c6c5022c8b1fc1
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ML classifier and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to potentially harmful content. The presence of these links and the overall structure strongly indicate a phishing or SEO-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://arch.ua/ckfinder/userfiles/files/94031154817.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090a12813496---mefutikukide.pdf
    • http://csc0512.com/userfiles/file/20210705130643_m0kze2.pdf
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609b6c4669a48---97401179678.pdf
    • http://studiotecnicopinto.it/userfiles/files/73757749641.pdf
    • http://abwgulfport.com/uploads/files/72947728708.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/7aa882e0e36b5186f4d1bd5c2e34b19f/84986081494.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/1004ttf8sgiv6tu29i4nl83cdn/zadinotimemafolonetetin.pdf
    • https://shibbirs.com/media/files/77911107074.pdf
    • http://snbedu.com/uploadfile/file///2021080811560595.pdf
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a21376191dc---79081934597.pdf
    • http://ecohost.ru/pics/images/file/detulu.pdf
    • http://gsmontaggi.it/userfiles/files/68047820041.pdf
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/b21221c6bcf2aa0fffe4661fe61b68f3/resaripevetawubid.pdf
    • http://nousgarage.com/userfiles/file/vizeruge.pdf
    • http://4appsoftware.it/file/78380521061.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a438bc4df74---78148562827.pdf
    • http://leadershipcareer.kr/fckeditor/_upload/file/kedoxixos.pdf
    • http://xn--80aantfcaehjbxzf1m.xn--p1ai/userfiles/file/19335444608.pdf
    • http://xn--80age2amlc.xn--80adxhks/pics/images/file/gusekuvulenidi.pdf
    • http://pensjonatagat.pl/userfiles/file/julisezugupuj.pdf
    • https://ccichn.vn/data/upload/file/54271843412.pdf
    • http://zzliuxue.com/upfile/file///jibugirit.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=civil+engineering+technology+books+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d27c.bin
d35b4cd1341ec96b63abe6206b00bbb229c11e636b6142bdaf405b75b276ba84
pdf-font-stream PDF embedded font (sfnt) at offset 0xD27C 11180 bytes
font_01_sfnt_off0000ec37.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC37 16792 bytes
font_02_sfnt_off00010449.bin
0792d3c96a34889229ff4d1bdc853b00c47f5b30a6a86be7abcd8ef8d7ffa9df
pdf-font-stream PDF embedded font (sfnt) at offset 0x10449 16492 bytes