Malicious PDF — malware analysis report

Static analysis result for SHA-256 810d2c95241be7ea…

MALICIOUS

PDF

82.2 KB Created: 2021-09-15 23:46:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ceafef41403b245140bc24e89f116752 SHA-1: 831340768e2f67d7b2f2f922972f565187c88b18 SHA-256: 810d2c95241be7ea26efa10de345ac7d5d012d1ab309575c6d8a8aae5c0938a7
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which are hosted on disposable domains and appear to be part of a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely a phishing or trojan delivery mechanism. The presence of embedded URLs and the 'PDF_RANDOM_URL_LINK' heuristic further support this, suggesting the document is a lure to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/c8a5febb37209bbddb05e3c5c229bfea/kotal.pdf In PDF document text
    • http://www.euro-fly.eu/userfiles/files/gabosemelebavojijenes.pdfIn PDF document text
    • http://aurora-c.jp/files/files/44875458858.pdfIn PDF document text
    • http://ct-tci.com/cttax/userfiles/files/16004321485.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/7460655144.pdfIn PDF document text
    • http://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/37775743847.pdfIn PDF document text
    • http://aotwcasino.com/ckfinder/userfiles/files/patasixalukovi.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/fodazemawafigoko.pdfIn PDF document text
    • http://gocep.org/data/userfiles/files/legolomodatani.pdfIn PDF document text
    • http://teakdeck.pl/files/file/76657750927.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb8bcaeef6---tatabegemadubovo.pdfIn PDF document text
    • https://badoza.net/userfiles/file/43947420301.pdfIn PDF document text
    • http://355353.ru/userfiles/file/nipedavoxazuwoxi.pdfIn PDF document text
    • http://fotocaroli.it/userfiles/files/sufinevixinof.pdfIn PDF document text
    • http://onyx-innovations.com/assets/ckfinder/userfiles/files/13541488630.pdfIn PDF document text
    • http://brlairport.com/images/file/gilonaxifekagevijepekise.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109132148018772.pdfIn PDF document text
    • https://akemi.ro/hirek/file/62118852493.pdfIn PDF document text
    • https://helicopterleasingservices.com/userfiles/files/tujowizatilosa.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/5322797855.pdfIn PDF document text
    • http://kubak-ubezpieczenia.pl/userfiles/file/96038661255.pdfIn PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/35415824648.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=dragon+ball+z+shin+budokai+3+ppsspp+highly+compressedPDF 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_off0000d885.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD885 18172 bytes
SHA-256: 21dfbd7bbf0359da65bc12357606eefaae21f4fba4c685e3cb90fada62a8d3ab
font_01_sfnt_off0001079c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1079C 11540 bytes
SHA-256: 8b3566daf2fda0c8f5c3661ef47f85e0d82b448e5f4f9e5e837c74cbe4da673e
font_02_sfnt_off0001226b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1226B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1