Malicious PDF — malware analysis report

Static analysis result for SHA-256 40e133529593cc62…

MALICIOUS

PDF

70.0 KB Created: 2021-09-25 20:05:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e71d2d43a67a3a6847ab4a9a8a41395b SHA-1: ec7c5b9928b126556c5a2778c9c00824a2f884dd SHA-256: 40e133529593cc62831f2ba0d92ad7cf92ae802f6eb3dfa65bfe25b41672df12
104 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. It also features a link farm pointing to multiple compromised websites, suggesting an attempt to obscure the final malicious destination. The ML classifier strongly flagged this PDF as malicious, indicating a high likelihood of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://autoradiator.mn/uploads/ckfinder/files/boxenutarov.pdf In PDF document text
    • https://marljivo.hr/userfiles/file/64355211070.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/penizakiloderowam.pdfIn PDF document text
    • http://belovosushi.ru/files/demaxenawagesawerivudaji.pdfIn PDF document text
    • https://purevdavaa.mn/uploads/ckfinder/files/limuniwazezamov.pdfIn PDF document text
    • http://devison-matras.com/upload/file/dafulibin.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/vilupekimozufij.pdfIn PDF document text
    • https://nirkongrp.com/ckfinder/userfiles/files/tavunufonetejawanubuwax.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370d8492487---naxezerutulikirized.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/xegosinexijeledosumi.pdfIn PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__613117956EDEE.pdfIn PDF document text
    • http://litroshaber.net/resimler/files/76105187952.pdfIn PDF document text
    • https://parfumzone.ro/files/file/bufidukawoji.pdfIn PDF document text
    • http://dspec-car.com/js/upload/files/93253773032.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/pogefezafotonexikewidukad.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210925_52797A0A110F366F.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/30937600357.pdfIn PDF document text
    • http://mylivediamondinventory.com/uploads/files/lavepagok.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/82c33c5b87fcd343929b7127844beeda/80364702115.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fec3029f35---52314103816.pdfIn PDF document text
    • http://salt17.com/userfiles/files/sulidopomilixodozeze.pdfIn PDF document text
    • http://centronegozi.com/public/58859576237.pdfIn PDF document text
    • https://siltri.com/fck_upload/file/xibizudibozurujofateri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=borderlands+3+playersPDF 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_off0000b061.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB061 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c873.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC873 16448 bytes
SHA-256: d03e5a5ffcba243d1cdf56d8eefbc784dbd256ba8205bf4e20bc0ef2f4ab4a6d
font_02_sfnt_off0000f2a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A3 10536 bytes
SHA-256: 70ce64692cf44ab4fc3fd1e8fa165fca92cfeb6694ff7a403a45510264819c5e