Malicious PDF — malware analysis report

Static analysis result for SHA-256 cefb4d8dec327c0f…

MALICIOUS

PDF

84.4 KB Created: 2021-09-15 16:19:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 2d291da1ee5d7910c487dec40001128e SHA-1: 259b6c74fb2906516400f166b43cc629ac0315b5 SHA-256: cefb4d8dec327c0fecd7cc898f9831ac453605c2e3a794c8554f4f48ef1a1329
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a link farm on disposable hosting. The embedded URLs and PDF structure suggest an attempt to redirect users to potentially harmful content. While no scripts were explicitly extracted, the PDF format often utilizes JavaScript for malicious actions, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://angkoronetour.com/userfiles/file/sofudujil.pdf In PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/4964679586.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/moduwijujuluwelikuwezedo.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613de7f608a0d---29906230461.pdfIn PDF document text
    • http://teresachild.com/upload/files/digajusul.pdfIn PDF document text
    • https://loyalangkorapartment.com/userfiles/file/boxawevelemelozalaxew.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/didodo.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/29599897507.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613019fd22d03---90215702773.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/40024956656.pdfIn PDF document text
    • https://www.cascatai.com.br/ckfinder/userfiles/files/lorutalomugipudoligeneno.pdfIn PDF document text
    • https://perfumes.dropship-tracking.com/userfiles/files/tiwukoxezaxetelemamafela.pdfIn PDF document text
    • http://www.gleason.com.au/application/third_party/ckfinder/userfiles/files/gewajapupogikanulina.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/66306666142.pdfIn PDF document text
    • https://everestart.com/images/stories/file/wudole.pdfIn PDF document text
    • http://murasakijr.com/uploads/files/28239425828.pdfIn PDF document text
    • https://rcot.org/userfiles/file/pagurudufavow.pdfIn PDF document text
    • http://myflora888.com/ck_files/files/kewojuzopuwasexowuzakojo.pdfIn PDF document text
    • http://etenindex.nl/images/uploads/88514125129.pdfIn PDF document text
    • https://0922.sproname.com/files/userfiles/files/12596567004.pdfIn PDF document text
    • https://speakingparrot.com/upload/ckfinder/files/173522632.pdfIn PDF document text
    • https://pankajplast.com/ckfinder/userfiles/files/xuwarinoket.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/73670435987.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/puwimigetijifakorelo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=marbury+v+madison+opinion+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_off0000e574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE574 10796 bytes
SHA-256: a024a0c476615722bb23fd63d93a2c47570d656635f96651dc37d6374424c8d5
font_01_sfnt_off0000fe11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE11 17736 bytes
SHA-256: 27b63e34704d028ba63791bf5cd1235fd7bce1439e206402c53cea2fcc9d306d
font_02_sfnt_off00012ba4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1