Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9b7a10e6f9ac86d…

MALICIOUS

PDF

71.0 KB Created: 2021-09-15 11:01:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 12cc2eaacc5c84ae2792b0299dbd5757 SHA-1: ae43badc4948e8d50acfa74e1e7ed727083408e5 SHA-256: a9b7a10e6f9ac86d22479eb7462ba711232537334b9d5d9341032d1155111d9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains a link farm with numerous external URLs, many hosted on compromised or disposable domains, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with exploitation or redirection to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://eros-arena.name/eros/userfiles/file/nuzipixadolazipugefinulor.pdf In PDF document text
    • http://remont-etalon.ru/upload/files/pezajagofi.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109121227114670.pdfIn PDF document text
    • http://pmke.cz/pictures/files/mojinaguzolowijoxaxud.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16140370a9a3d2---zodurezikeka.pdfIn PDF document text
    • http://mxag.com/upload/browse/file/nemuvitamolilidamotowuwak.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/89948785797.pdfIn PDF document text
    • https://unitytradefze.com/ckfinder/userfiles/files/buxarunimunabajafexija.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/36314262188.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/zedazugu.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/kukakutowuzomun.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/94372904524.pdfIn PDF document text
    • http://9meclinic.com/ckfinder/userfiles/files/87805190030.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/femowuwabutebibaxalikafip.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/milaxelanefe.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/dcd747dd3e9b0b8268d75947d7833cd0/50309250816.pdfIn PDF document text
    • http://blgjad.com/upload/files/56093205490.pdfIn PDF document text
    • http://nigerseedindia.com/uploads/93165173641.pdfIn PDF document text
    • http://gugugroup.com/userfiles/57198586395.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/66713648466.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613fdb015f2a2---wubawefanap.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/31323135204.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16134f8903cf58---40986210690.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=unique+android+launchersPDF 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_off0000b623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB623 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE35 15928 bytes
SHA-256: 956b38a331726151c10c163b94c946b0dabbd802d4effa36a8fa6403474ac3c2
font_02_sfnt_off0000f724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF724 10624 bytes
SHA-256: f5de810039346dc4621ca3e935d15d0554003a5d7acb2be824ca34e292049354