Malicious PDF — malware analysis report

Static analysis result for SHA-256 61f72e6d0078c1c8…

MALICIOUS

PDF

76.6 KB Created: 2021-09-17 22:30:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e546a09b92f928caa5af9e19e069a0f7 SHA-1: 16348146d3578ab036821d393c9b5f1896d1d4a9 SHA-256: 61f72e6d0078c1c833233c228411d690af4fbacadd7cf4966f719586fd3e5b2a
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many pointing to other PDF files on distinct domains, indicating a link farm or redirection scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a non-clustered link farm on disposable hosting. The ML classifier and ClamAV detection confirm the malicious nature of the PDF, likely intended to lure users into downloading further malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://bikaji.zohukum.com/ckfinder/userfiles/files/vibokuropesofegepe.pdf In PDF document text
    • http://olgapolyakova.com/files/files/85298078315.pdfIn PDF document text
    • https://ancoraeducacion.com/images/94891595252.pdfIn PDF document text
    • https://alarouba.com/ckfinder/userfiles/files/99020036597.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/1469864994.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/85666961869.pdfIn PDF document text
    • https://akilanews.com/ckfinder/userfiles/files/12456128344.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137cac25137b---67251031886.pdfIn PDF document text
    • http://apsons.eu/files/file/gapazegotudutevikono.pdfIn PDF document text
    • http://cl-pub.com/files/files/xatubun.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/488661185.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/27742722018.pdfIn PDF document text
    • http://autothudo.vn/upload/fck/file/43527360323.pdfIn PDF document text
    • https://zabulgaria.org/userfiles/file/78342510523.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/vuxatefikinur.pdfIn PDF document text
    • http://architetturaurbanistica.it/userfiles/files/kijoj.pdfIn PDF document text
    • https://kuni.ro/app/webroot/files/userfiles/files/37415807325.pdfIn PDF document text
    • http://bk-plus.at/userfiles/files/zokom.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210902073449.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=original+led+tv+price+in+pakistanPDF 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_off0000c823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC823 17396 bytes
SHA-256: d6d82e58c201b9c52ae20d7424f2f8b3e860518975a087fd706997826c93b58a
font_01_sfnt_off0000f4b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC8 10752 bytes
SHA-256: 5c4b60677c6dc742c5acf59923988d2138c40c7e86592ff3432fe6551742f30b

Open this report in the interactive analyzer, or submit your own file for analysis.