Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8e2dcadad680270…

MALICIOUS

PDF

78.9 KB Created: 2021-09-12 16:16:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cf32f7da77b9d769e1b9dd1a2fea366d SHA-1: 2eb92145b27a9267538709dd246ed27c32086261 SHA-256: a8e2dcadad6802708181ea59a0c3b3549153d651887e62be77a933554aeaeb4f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to unknown or potentially malicious domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a link farm designed to obscure the true destination, a common tactic in phishing and malware distribution. The ML classifier and ClamAV detection further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://tonthephunglan.vn/upload/files/zudorikojoriveludikolob.pdf In PDF document text
    • https://thaiwoodengames.com/files/upload/files/sokogivomutuvomaxomewo.pdfIn PDF document text
    • https://mytopics.it/uploads/file/xapofetepamekuzogalumil.pdfIn PDF document text
    • http://internet-trade.cz/UserFiles/file/82075816133.pdfIn PDF document text
    • http://zzfcw.com/file/fkimg/file/36711592332.pdfIn PDF document text
    • https://ms02bet.net/contents/files/57945867998.pdfIn PDF document text
    • http://sincaremedicaltour.com/js/upload/widaveleza.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/1450042210.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/60869329242.pdfIn PDF document text
    • https://emartdeko.pl/galeria/file/kerefofiderefof.pdfIn PDF document text
    • http://vin-baietii.ro/ckfinder/userfiles/files/xejimofananakaxajef.pdfIn PDF document text
    • https://connatlas.com/home/conn/public_html/ckfinder/userfiles/files/kebim.pdfIn PDF document text
    • http://cmtl.in/uploads/userfiles/file/file/60605750518.pdfIn PDF document text
    • http://hodoan.net/userfiles/file/29979388276.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/1559329961.pdfIn PDF document text
    • http://wanyuantemple.tw/userfiles/file/zotedasuf.pdfIn PDF document text
    • http://carbontuning.ru/file/sovize.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/tuwofujofodomud.pdfIn PDF document text
    • http://js-space.de/userfiles/file/15343890756.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/misimirefokorawesogasib.pdfIn PDF document text
    • https://marbletreasures.com/uploads/image/files/32617347816.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137cadd5d499---75619315363.pdfIn PDF document text
    • http://livestocktool.com/d/files/kigororakonubopojawev.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/66484710336.pdfIn PDF document text
    • http://kunbot.com/upload/files/netepusa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=modern+physics+for+scientists+and+engineers+4th+edition+thornton+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_off0000cc8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e4a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A4 11036 bytes
SHA-256: 1a6035c607c29c59733d1fe1c85b60a9ed061ed48315827c2dae860c6c83edb3
font_02_sfnt_off0000fe22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE22 18180 bytes
SHA-256: 6028d645084dea47bb717b1f39514f6f5ed726d6a672992d4145eb8e0e37e5e5