Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a9e3459fc457d4f…

MALICIOUS

PDF

91.0 KB Created: 2021-09-08 13:34:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 597b21d9c2634c983514eb2efa9244cc SHA-1: 7edc1aa33fd34a0f37739d46896f30d3ba2e55de SHA-256: 2a9e3459fc457d4fac8b25b1de866c37da7de3919ee665851a4447cb893ad694
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to external URLs, as suggested by the PDF_URI heuristic, which are often used for phishing or downloading further payloads. The sample's structure and the presence of numerous external links point towards a link farm or redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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
  • 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://telewebmarketing.com/FCKeditor/file/tagikejewusirowerigeji.pdf In PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161328230a6e17---34444144485.pdfIn PDF document text
    • http://thetsaban3watnuea.com/UserFiles/file/95223221959.pdfIn PDF document text
    • http://lukinserv.hu/file/nagonozu.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/91779514997.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/razosep.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/vakodozobalowawob.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/45058413431.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/41121140773.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/zonugibabilesoduj.pdfIn PDF document text
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/pazetazadositen.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/56680040066.pdfIn PDF document text
    • http://peneleos.pl/userfiles/file/15842627468.pdfIn PDF document text
    • https://www.bankkartya.hu/js/ckfinder/userfiles/files/rebat.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/kimanuwufav.pdfIn PDF document text
    • http://espressobuilders.com/app/webroot/files/userfiles/files/potev.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/4059310044.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/20390003113.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/61312525882.pdfIn PDF document text
    • http://parbatsamajjapan.com/img/files/files/bazof.pdfIn PDF document text
    • http://vinczeandlaszlo.com/upload/42426132645.pdfIn PDF document text
    • https://www.travelknowhowscotland.co.uk/assets/js/ckfinder/userfiles/files/38920426266.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/64348930566.pdfIn PDF document text
    • http://bkm-market.net/userfiles/file/4932642072.pdfIn PDF document text
    • https://www.andreivieru.com/ckfinder/userfiles/files/buralorivixudovowidure.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=derecho+internacional+publico+peru+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off0001419b.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1419B 17516 bytes
SHA-256: 73ef8fdd9f276350b593ac78fa5dc7b22af1b53e97601c0e8221c31928cb62fd
font_00_sfnt_off0000e0ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AD 18816 bytes
SHA-256: 6c88ae348147311103157263f19aa3003b641cca14524d15caff63b5f503cf03
font_01_sfnt_off00011107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11107 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001291e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291E 10792 bytes
SHA-256: 38710f71db6e984fc012935e4bd1cac8d0550965273f5cb15e6fa8e58a02cf6b