Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5520098c1ba1d07…

MALICIOUS

PDF

81.8 KB Created: 2021-09-13 03:56:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 784e2946d57f903ef62deace1f6450e8 SHA-1: 9ecec90b0ee555f051902614ddb45ddb710735a0 SHA-256: a5520098c1ba1d07b991d4b28f74826f3717712d50c99c3a4bd3f47d3aefb5c9
174 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating malicious intent, including random URL links and being flagged as a link farm on disposable hosting. ClamAV detection and ML classification further support its malicious nature. The presence of a 'download button' lure suggests the document aims to trick the user into downloading a secondary payload, likely hosted at one of the extracted URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/e0727abea1422a04568be1c6f99af14a/bexozudijadapujedo.pdf In PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/46973984265.pdfIn PDF document text
    • http://ricettebiagi.it/uploads/assets/file/boviposef.pdfIn PDF document text
    • http://onelove.cz/file/wudesanabuvifavejir.pdfIn PDF document text
    • https://livewireeventz.com/userfiles/file/wigodi.pdfIn PDF document text
    • http://twtqedu.com/userData/ebizro_board/file/97516534587.pdfIn PDF document text
    • http://ranahytta.com/ckfinder/userfiles/files/wugoponotaripezamulus.pdfIn PDF document text
    • http://hengtongrongshang.com/jingkelun/userfiles/files/20210912015218.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/rebel.pdfIn PDF document text
    • http://status.cz/UserFiles/File/xutavijafubixakosulotexa.pdfIn PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/97213064810.pdfIn PDF document text
    • http://imbirimbir.ru/files/nekufenemaj.pdfIn PDF document text
    • http://yongchengtech.com/uploads/files/202109121053449918.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/semupeta.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16138d36850165---86846591003.pdfIn PDF document text
    • http://ephtour.com/FileData/ckfinder/files/20210908_D7AD71B92DB77C6B.pdfIn PDF document text
    • https://gujaratisamajparis.org/upload/files/duxubibuxebupan.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/90648364949.pdfIn PDF document text
    • https://ecodiagnost.com/ckfinder/userfiles/files/31943352544.pdfIn PDF document text
    • http://phaptangpgvn.net/app/webroot/upload/files/91087963966.pdfIn PDF document text
    • https://ph789.com/pinhsuan/files/file/45090680082.pdfIn PDF document text
    • https://etre-cheval.fr/Applications/MAMP/htdocs/etre%20cheval/news_pix/file/78406667207.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/6838fc4758534098d0f1406bf6c2e1d2/9225903925.pdfIn PDF document text
    • http://russkiivopros.com/images/FCKeditor/file/resivuworigadu.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/vubipodajud.pdfIn PDF document text
    • http://carraracucinecomponibilitrapani.it/userfiles/files/xokerazizaraxarefalus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=pokemon+delta+emerald+rom+hackPDF 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_off0000da91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA91 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A8 10468 bytes
SHA-256: 5c2e6914010721664575c700ab90147d4732b0751c5676c82933c445ceaecfb3
font_02_sfnt_off00010a41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A41 18200 bytes
SHA-256: fdbfc948b33dd71e0123921c1088ce16e693aff368fa77b74c42e1bda5647158