Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3f5cae7cdf2575…

MALICIOUS

PDF

83.5 KB Created: 2021-09-19 14:58:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 97b9104a3d4f3af5381293f7ac34d889 SHA-1: 14e6f3582ff28ea680f53061713f7335c80b924f SHA-256: ac3f5cae7cdf257529469e7d69076260507f2acdd96c927c6fde268ca989a425
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to multiple PDF files hosted on various domains, some of which appear to be compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to obscure the true malicious destination. While no scripts were directly extracted, the overall structure and heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://casasholidays.com/scgtest/team-explore/uploads/files/8943273802.pdf In PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/piwibitosojefomejakofa.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/xifeke.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/vabivakawile.pdfIn PDF document text
    • http://storemisr.com/uploads/files/pojovazelugaverutazak.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/62979460818.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614311ec3adc3---mebupe.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614002d03e798---58236291864.pdfIn PDF document text
    • http://drigungkagyurinchenpalbarling.org/upload/userfiles/files/91431289237.pdfIn PDF document text
    • https://www.area-tlc.com/public/ckfinder/userfiles/files/kogow.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5fff0fcb054f71825f713caf3b3d24e7/tavepixorutowamaji.pdfIn PDF document text
    • https://windfreeklima.com/upload/ckfinder/files/17316617227.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/45117566327.pdfIn PDF document text
    • http://mibenjamin.com/userfiles/file/71567710447.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/vakejojinivi.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/521b3b0240bcbdbddf7e750901e1772b/rotigefogosubalepomep.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/3fc3302edcce58aecb3a1ecedc8588f3/tudewaruxefetugagako.pdfIn PDF document text
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13557353321.pdfIn PDF document text
    • https://pacantioquia.org/aym_image/files/tudegejovetes.pdfIn PDF document text
    • http://gelikonline.ru/content/Files/47688123209.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140fc7cf169b---28996742227.pdfIn PDF document text
    • http://slsnn.ru/content/file/32527761669.pdfIn PDF document text
    • http://elcwma.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/5013153022.pdfIn PDF document text
    • https://perfecthospitals.com/FCKeditor/file/nomoloma.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=video+share+movie+app+downloadPDF 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_off0000e2a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2A3 10680 bytes
SHA-256: 2d54d7bfa78a9b4a171ed78d27d0df41e890ea559467b786ca3ac6a4b2abbb30
font_01_sfnt_off0000faf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11305 17712 bytes
SHA-256: c5a74b58622e4f37bacccef931fb8c7fecbf886b4b264bb21733e5ce7867e6b6