Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e809fcbaf28f183…

MALICIOUS

PDF

73.4 KB Created: 2021-09-11 23:50:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 19d65ea65e5074437eb562151cf52510 SHA-1: 57623334dcb8511cbb0a1c10d4c2127fc4eeb3e3 SHA-256: 8e809fcbaf28f183cd03c9a50735662956669b4e97798a1444d7c68f6491bd3e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URI heuristics and link farm indicators supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://netron.pt/app/webroot/media/files/kujixewevufubujapi.pdf In PDF document text
    • https://erdenetpost.mn/userfiles/files/zonok.pdfIn PDF document text
    • https://akilanews.com/ckfinder/userfiles/files/rofabadekigigapenevafovef.pdfIn PDF document text
    • http://asustainable.com/global/file/wukiz.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/ok2cdfsqa1kl2vd623t9uo85kd/40344930816.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210908095723742.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134dd1764933---kijefifegezo.pdfIn PDF document text
    • http://lamay.de/userfiles/file/jukubadawafi.pdfIn PDF document text
    • http://www.pro9apps.com/app/webroot/files/uploadimagesfile/pepadugif.pdfIn PDF document text
    • http://nutrizionisti.eu/public/thread/risorse/file/59465351748.pdfIn PDF document text
    • http://belgium-ex.com/images/blog/file/pomazakewuguzuruporovubo.pdfIn PDF document text
    • http://defhjdrjioo.friend-match.com/upload/files/77138767732.pdfIn PDF document text
    • http://eaupureinternational.com/userfiles/file/nasiruzafapixawavuwewux.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/41065619042.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/bokub.pdfIn PDF document text
    • https://nissanzorba.ro/ckeditor/ckfinder/userfiles/files/55222295350.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/zexeluw.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/nisosu.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/1242446070.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/rubarudowoxukobapexoz.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/riwoxu.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210907_7F798AE4AA1DF912.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ccd1c14a8---sivunataruwin.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/binon.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/nodebesel.pdfIn PDF document text
    • https://5ky13lu3-1251.com/contents/files/23965560951.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=social+psychology+11th+edition+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_off0000bd18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD18 11040 bytes
SHA-256: 4f0f623179f0e7a9e91c0a64ded1143f8d6898ea8ddc221f0f5f35d5e59fc5ee
font_01_sfnt_off0000d695.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD695 16132 bytes
SHA-256: d27feaadd90fdd3c043c9c452cc0d96b242e25a3ad2d49309e795ff7fb1363d8
font_02_sfnt_off0000ffaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1