Malicious PDF — malware analysis report

Static analysis result for SHA-256 528500a411df6b22…

MALICIOUS

PDF

82.3 KB Created: 2021-09-19 07:12:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5ebb80a0bb0ef43cda3c58a78aac816e SHA-1: a7e476bc0b09b9bbeae706d5483d6b1c7ec6eaf2 SHA-256: 528500a411df6b22dd61c7039a8fb394a1c3a00f1ba156ca753acf36ea05db0c
166 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as a phishing trojan and exhibits characteristics of a social-engineering lure, specifically prompting the user to install a browser extension or update. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to malicious sites or download further payloads. The presence of numerous unknown URLs, many ending in .pdf, indicates a link farm designed to obscure the ultimate destination.

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 http://thermcom.cz/userfiles/file/vavobesonupabenirid.pdf In PDF document text
    • http://maroba-zirndorf.de/file/13546494168.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa6bd28d35---73990472968.pdfIn PDF document text
    • http://nomorecpapmachine.com/userfiles/files/57462134230.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7c69f2660---rulipe.pdfIn PDF document text
    • http://gartenbaukoeln.de/uploads/files/12891493083.pdfIn PDF document text
    • http://lamekatus.com/uploads/ckeditor/files/38543326548.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/85382400329.pdfIn PDF document text
    • http://romanasulcikova.cz/userfiles/fawabazaxikokovixaretufok.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/55863483611.pdfIn PDF document text
    • http://gayaarchi.com/userfiles/file/20210906124811.pdfIn PDF document text
    • http://abarappresentanze.it/userfiles/files/jomal.pdfIn PDF document text
    • http://xn--80akazwaeiw.xn--p1ai/editorfiles/file/wekonekunodokabizivemaku.pdfIn PDF document text
    • http://huntland.hu/upload/file/bolas.pdfIn PDF document text
    • http://mizuho-co.net/file/ck/files/80223311186.pdfIn PDF document text
    • https://officialbacknumber.org/editor_up/85352717677.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/tomunovavoduzamuzalum.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/gasolulabalivemixivik.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/seravetulu.pdfIn PDF document text
    • https://ystechpro.com/nbloom/fckuploads/file/21081251818.pdfIn PDF document text
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/kopew.pdfIn PDF document text
    • http://stensoproject.com/userfiles/files/riguw.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/sigapidimiwagudakudetiza.pdfIn PDF document text
    • http://spprp.pl/userfiles/file/53839274467.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+use+socks5+in+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_off0000d8ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E0 18880 bytes
SHA-256: 4440d879227520d392c26eb71ae82ebba08101e35756e550f4bb9fddba31b8e6
font_02_sfnt_off00012264.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12264 10720 bytes
SHA-256: 3cf1c7560eefa12e272181132e198751ae2b95a6e69ed57307cc5b3879a05f20