Malicious PDF — malware analysis report

Static analysis result for SHA-256 43e9d1c7a8efef99…

MALICIOUS

PDF

75.3 KB Created: 2021-09-17 21:24:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d13d53263475848b9f10edabf4b212ef SHA-1: eb10ef19703d598953f7b61322d197b2f74c339c SHA-256: 43e9d1c7a8efef9953129946e1639a070028a87414210fc8ccf459df23fb22b5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. The PDF contains numerous embedded links, many of which point to disposable domains or are structured as link farms, suggesting an attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • 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.
  • 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://valleyrentals.com/userfiles/file/jinar.pdf In PDF document text
    • https://emmaushuis.org/pages/21027171682.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/21122630250.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/d4344372c4e27145752c2786133045b0/ninenepanawuxo.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/161441de474231---32227330930.pdfIn PDF document text
    • https://alternativi.brtim.com/uploads/wysiwyg/files/masovekenaxi.pdfIn PDF document text
    • http://bfcy88.com/uploads/files/povujefixilosobod.pdfIn PDF document text
    • https://easy2ticket.com/upload/files/rotudodo.pdfIn PDF document text
    • http://clubsahdianagalati.ro/upload/editor/file/72470191912.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/kikuvuzodiraluvigurokufo.pdfIn PDF document text
    • http://eksternest.be/images/file/72725035247.pdfIn PDF document text
    • http://fusiongrup.ro/userfiles/file/fanovadudenuv.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/96228240946.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/78374119177.pdfIn PDF document text
    • https://lrdreamteam.com/files/files/file/InfoProduct/file/43769567572.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/falatujilev.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/buvipimevunisojetevof.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/33619591656.pdfIn PDF document text
    • http://gat-asset.com/CKEdit/upload/files/lixodonasenamipimoturojo.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/88931575917.pdfIn PDF document text
    • http://datavincity.com/uploads/ckfinder/files/9955046824.pdfIn PDF document text
    • https://ltes.tw-goods.com/UserFiles/files/sizin.pdfIn PDF document text
    • http://sun-dr.com/uploads/files/202109152316596427.pdfIn PDF document text
    • http://p-itos.net/admin/userfile/image/file/99211653006.pdfIn PDF document text
    • https://swift-tw.com/lcc/upload/files/kalagajubuz.pdfIn PDF document text
    • https://curvy.tw/upload/files/1102878934.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=minecraft+1+16+220+apkPDF 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_off0000bece.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBECE 18412 bytes
SHA-256: f3a79b8c4e411f4db45238bd02c63ec23b3eec9297dd728e7601f915b378c537
font_01_sfnt_off0000eed8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED8 10684 bytes
SHA-256: 5b912b704d0a69976230aea55ac097e03e4804d8822f2b6283e2965687f1f13b
font_02_sfnt_off00010799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10799 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1