Malicious PDF — malware analysis report

Static analysis result for SHA-256 76fd8ec4565471f5…

MALICIOUS

PDF

74.1 KB Created: 2021-09-19 01:12:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 90fb0fd2dee4374846232cec2e799a8f SHA-1: f2e5785caa28ee43417cacaa69ca67d13ae39f86 SHA-256: 76fd8ec4565471f5597f1f904ae70744cd870bf1cde325d14ab9a45a06007a55
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a critical heuristic firing, which is often used to execute malicious actions. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates the document is part of a link farm, and the numerous extracted URLs, many pointing to PDF files on various domains, support this. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users into downloading further malicious content or engaging in phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://opsir.eu/files/file/28539671486.pdf In PDF document text
    • http://www.portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/51459289936.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16133fc959a026---25761844528.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/kilabawutuworasediduk.pdfIn PDF document text
    • https://adeptos.clevercloud.pt/images/items/files/55972007179.pdfIn PDF document text
    • http://thegioixedap.net/upload/files/rovunusabezoxegolasude.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/17934577005.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/tudigu.pdfIn PDF document text
    • http://jumpinfit.it/userfiles/files/likudexoxiwonelopiximus.pdfIn PDF document text
    • http://okuninka-biale.pl/userfiles/file/livewofimamiral.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/pekasoxuzepogaradek.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/161354a0714289---7461087853.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/43867821021.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/nagipizexesuxuvuzepobejo.pdfIn PDF document text
    • https://mehfermobilsaglik.com/userfiles/file/23556850328.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/83029579194.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/fakimavofo.pdfIn PDF document text
    • http://coumert.com/images/file/49496217330.pdfIn PDF document text
    • http://www.neoneofitou.com/ckfinder/userfiles/files/44790233521.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/sekununusamuza.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/14702925859.pdfIn PDF document text
    • http://seritour.com/rsm/files/nikejizarapejupiv.pdfIn PDF document text
    • http://myapartment.de/web/editor/files/bonid.pdfIn PDF document text
    • http://4bx.pl/public/file/vironepaduni.pdfIn PDF document text
    • https://nyig.com/files/file/75326816134.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=print+page+save+as+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_off0000c255.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC255 10572 bytes
SHA-256: e61ea8fe4eecf441311da11db9f803e7ec864602c4bf871045f394c7c2a3c641
font_01_sfnt_off0000da62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA62 15896 bytes
SHA-256: d0e279d6d2da69e9735e7243f9b2347f26aca8af8f53d50fffd896897793e397
font_02_sfnt_off00010346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10346 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1