Malicious PDF — malware analysis report

Static analysis result for SHA-256 f760d5c44e0fc14d…

MALICIOUS

PDF

71.4 KB Created: 2021-09-12 04:01:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fc9143497ba966c245692371f68e4ec0 SHA-1: ab7f5e16336b89e848f1ba3dc7a14b552e6c552b SHA-256: f760d5c44e0fc14d4ec316ce864b7feb3701fccfdc98a839f6665f4b45440570
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external domains, many of which are identified as disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to serve as a lure for further malware downloads. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 http://panda-es.tokyo/yamituki-n/uploads/files/99175337366.pdf In PDF document text
    • http://ldkxzzs.com/images/userfiles/file/11807583917.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/mafizakenoxulunipupakage.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/38820455588.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/limufekanurepato.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/dinirugikatifaf.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210906155049.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/lifezivuxowiwepudigenifa.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16135face731e1---zanizobajonagol.pdfIn PDF document text
    • http://tms-technology.com/ckfinder/userfiles/files/kozuj.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/91033329013.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/nusiguwavopabutovogebepot.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/zirusu.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/pajineluvo.pdfIn PDF document text
    • http://harringtonassociateslaw.com/Test/JabzMedicalBillingService/userfiles/file/jegupizopinefotesanara.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/muxazokisufabetozik.pdfIn PDF document text
    • https://www.informacion-indoorclub.com/boletines/img/file/sasizujepilolapajafaful.pdfIn PDF document text
    • http://qwerty.pl/_data/file/josunuzopirogeraxizopalo.pdfIn PDF document text
    • http://kolbiko.com/images/uploads/file/sazagebotix.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/mujigik.pdfIn PDF document text
    • http://onlinevay.com/upload/files/xurapukex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=delete+system+memory+androidPDF 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_off0000b604.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB604 16360 bytes
SHA-256: e36eb766dce17de6dde6068c2ce4d3594363e2ab790c5e555b5dc6a8daa98912
font_01_sfnt_off0000e00c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF823 10524 bytes
SHA-256: f862fc1af873da72202da7945165df327031dc82b220bfe7f13e7fcade6f7f1d