Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a2671489720f701…

MALICIOUS

PDF

78.3 KB Created: 2021-09-14 11:57:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 56de47af661a9e96bdf54b9741e3d764 SHA-1: a77579a57e63fd9f3cc137b7ea28ed33bae797a3 SHA-256: 4a2671489720f70148b780572e2667909d4530728789d3ad81c8b8171460496e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to disposable domains, which is characteristic of a link farm designed to host malware. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to deliver a phishing or trojan payload. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to trick users into clicking malicious links, potentially leading to the download of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://bonvoyageindia.in/ckfinder/userfiles/files/44977998694.pdf In PDF document text
    • https://dottoridegregorio.it/public/file/xofuvazefebuluvipurusud.pdfIn PDF document text
    • http://workontext.ru/media/file/muruxopalufomekolojide.pdfIn PDF document text
    • http://danchrisjewelry.com/userfiles/file/pivatipeze.pdfIn PDF document text
    • https://www.opsclown.it/ckfinder/userfiles/files/xurujuzepujepofifedug.pdfIn PDF document text
    • http://ilovechardonnayhills.com/userimages/sijazofaf.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/28540275252.pdfIn PDF document text
    • https://mertlakustika.cz/images/pages/file/baxukexifik.pdfIn PDF document text
    • http://kbinteriery.cz/userfiles/file/novar.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/49947745502.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sadoresazukewepuno.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/61555254172.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/xizegubojo.pdfIn PDF document text
    • https://hensuyenpqa.traigiongthuha.com/ckfinder/userfiles/files/gugusedezaruruti.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/basazuvasetedono.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16134e6949422a---xisujifizoratawa.pdfIn PDF document text
    • http://thesecurityguardunion.ca/userfiles/files/sakitewotelelopedusivinu.pdfIn PDF document text
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/13141727071.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/fudefoxokamugikadozoz.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/dafejavirajuxoxipi.pdfIn PDF document text
    • http://paoladebenedetti.eu/userfiles/files/texararikubufa.pdfIn PDF document text
    • https://sunnyvale.com/wysiwygfiles/file/jigujuzuvolevike.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=farm+city+mod+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_off0000d0c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C5 16800 bytes
SHA-256: c73a410125c5dceb578e7d259f73e532ec6a22d95cc3ab55895b566dd396bee1
font_01_sfnt_off0000fc94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC94 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000114ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114AB 10408 bytes
SHA-256: b421ea095af33372c9c1725973746a39d5f0c5dd83f50f45661fbf901d2f8658