Malicious PDF — malware analysis report

Static analysis result for SHA-256 39aca5d77eb2f721…

MALICIOUS

PDF

77.9 KB Created: 2021-08-19 11:25:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: da500b47a235fa3d3484ff7fd6c97583 SHA-1: cfdcf26bad47ac080116b5a1fb254dce3b218871 SHA-256: 39aca5d77eb2f7211920fed67aec95d6622991ba554fe92a2e1c0d06d28363e5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or directing users to malicious content. The presence of link farms on potentially compromised hosting suggests an attempt to obscure the final destination or leverage existing vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b56853799db---kinafokizefozaz.pdf In PDF document text
    • http://kristenpell.com/userfiles/files/77769882775.pdfIn PDF document text
    • http://xn--h1aaebbkfib4a.xn--p1ai/sadm_files/levajixozejevewolurajisu.pdfIn PDF document text
    • https://magyar-logyogyasz.hu/fileok/file/30410989852.pdfIn PDF document text
    • http://jysfh.com/upload_fck/file/2021-8-16/20210816184157212408.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/54556098094.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c43140c8d2---8519616766.pdfIn PDF document text
    • http://jmdfhjl.com/fckeditor/userimages/file/22338668568.pdfIn PDF document text
    • http://goldsunjsc.com/upload/files/ramomudinukisubudetat.pdfIn PDF document text
    • https://preciseenergygroup.com/media/41310323317.pdfIn PDF document text
    • https://thekolkatapackersmovers.com/ckfinder/userfiles/files/11612177091.pdfIn PDF document text
    • http://zzquansu.cn/d/files/kiwovubakuletam.pdfIn PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/57972528203.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/50652787410.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/9ov7mpv3j0n46nv3fn5c2h64h3/73807172320.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/59452526746.pdfIn PDF document text
    • http://edanieltour.com/FileData/ckfinder/files/20210609_DC43C1E8A290E24A.pdfIn PDF document text
    • http://londonjip.com/userData/board/file/dagowezavurit.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/57509071243.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/sarunavet.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/dg21p44381llbiu1ggjosdbg2r/puvedaxogabesema.pdfIn PDF document text
    • http://grupophi.es/uploads/files/48713352595.pdfIn PDF document text
    • https://bigpointpin.com/calisma2/files/uploads/duvute.pdfIn PDF document text
    • http://csc-028.com/userfiles/file/20210723201158_tdbbhg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=what+is+the+class+enrollment+key+for+turnitinPDF 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_off0000cda8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e5bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5BF 10900 bytes
SHA-256: 6da11e67b049981daca8422d3f59c225cae5863158e57728e3cff45e5fa439b5
font_02_sfnt_off0000fed1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED1 16452 bytes
SHA-256: 0e8686aab6399ffa6a63032e07fb3f2b3117d11618a4f81aea67aa9642632bdb