Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f16a26102e55c21…

MALICIOUS

PDF

85.8 KB Created: 2021-09-22 14:43:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bfb24741eae68d2a026e7dff6e7ca7dd SHA-1: 10ff5b32d22db163731c897508dbc1e4662ee92d SHA-256: 1f16a26102e55c21b2304f5f4fffc092f71d3d372fee3c2c94df3ed557c7460b
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'SE_BROWSER_INSTALL_LURE' indicates the document's content is designed to trick users into installing malicious browser extensions or updates. While no scripts were directly extracted, the presence of numerous external URIs and the nature of the lure suggest the document likely attempts to download and execute a second-stage payload, potentially leveraging JavaScript for execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://philabc.ru/uplcv?utm_term=dark+theme+for+chrome+browser PDF link annotation
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161468bfb43d72---wizafogolarijarasasixafod.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/47572754424.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/61114750785.pdfIn PDF document text
    • http://interiorconsignments.com/media/file/sevilusizumulivumoriposi.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/zobasidevigegaxite.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/xotefamepekov.pdfIn PDF document text
    • https://ikitellirezistans.com/upload/files/73697892966.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/digudubunapokafuwo.pdfIn PDF document text
    • http://przyrodnik-kujawy.eu/userfiles/file/76407848242.pdfIn PDF document text
    • http://back2wood.de/userfiles/file/17435176852.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/vivusaboketopopofemifo.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/72277166023.pdfIn PDF document text
    • http://podushka.by/files/files/81172396957.pdfIn PDF document text
    • https://diamond-marketing.cz/soubory/fegasa.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210916091335.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/20219191356241348.pdfIn PDF document text
    • http://na3.it/misc/file/biburogediwewolexevofi.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/25835887956.pdfIn PDF document text
    • http://yieldpharm.com/upload/files/dojowiwumetasakoj.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136e20f7fcc5---90149241070.pdfIn PDF document text
    • https://vinacoma3.vn/userfiles/file/pofavulos.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/tudalilofeg.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/64752916396.pdfIn PDF document text
    • http://domadoma.cz/userfiles/file/nusekaxirupazevaso.pdfIn PDF document text
    • 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_off0000e373.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE373 10680 bytes
SHA-256: a32beb79fd9a05a294b19a5aebfb8c8de48bcfb80f51ed6f672f7fc58d12f22c
font_01_sfnt_off0000fc13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11425 20264 bytes
SHA-256: aa9873c92ca6cee618e051ba741f3debf8a909ccd77a25d94642d6548f3c4b8d