Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a86cd21d8c39af0…

MALICIOUS

PDF

78.0 KB Created: 2021-09-12 19:10:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 83ff849fe9ffcdd9df261169f3d77240 SHA-1: 6f24023c214be49d9ec2cee74a85f07823a5960e SHA-256: 7a86cd21d8c39af0b5693579de5ccf33d5f476b6c0b13dd9990ace66093d1e64
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The document contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high likelihood of malicious intent, likely to redirect users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://primeasset.hu/fileok/file/20500343077.pdf In PDF document text
    • http://cck-brno.cz/ckfinder/userfiles/files/xozipofesozonaparotofuso.pdfIn PDF document text
    • https://newsru.md/upload/userfiles/files/xewugijitefuranobanakufiw.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0b94313b8---zogigejevofu.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/59420935990.pdfIn PDF document text
    • http://ashokarefrigeration.com/userfiles/file/xizogegoneketoxuloj.pdfIn PDF document text
    • http://rileyillustration.com/images/agency/files/pemafofokimek.pdfIn PDF document text
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/45424269241.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16133c9a9d1410---60664627695.pdfIn PDF document text
    • https://dildendilecevirievi.com/upload/ckfinder/files/51826088510.pdfIn PDF document text
    • http://holzweiss.at/wofepuxa.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/ruwovuvaletexa.pdfIn PDF document text
    • http://studiosantese.eu/userfiles/files/21907076582.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/zuwozawapap.pdfIn PDF document text
    • https://investir-petroleo.pt/ckfinder/userfiles/files/fenudizageti.pdfIn PDF document text
    • https://szelvedojavitasmiskolc.hu/files/files/33787654248.pdfIn PDF document text
    • https://zenit-npk.ru/files/file/19274731991.pdfIn PDF document text
    • http://thainightjob.com/ckfinder/userfiles/files/5118368884.pdfIn PDF document text
    • https://eko-briketes.lv/userfiles/files/14974908230.pdfIn PDF document text
    • https://mangalargalux.com.br/ckfinder/userfiles/files/95833060022.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/ligudiwodipozim.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/gamoxipepe.pdfIn PDF document text
    • https://soswzgierz.pl/web/uploads/files/pumenekujulubatubumimaka.pdfIn PDF document text
    • https://vnnc.vn/img-hdmedia/files/18691321906.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/94420206431.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=android+rpg+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_off0000cf11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF11 10196 bytes
SHA-256: 8a4b4388da4484bd5ba6aff5d8375c1d0d3865341774513d46eec969e42c1145
font_01_sfnt_off0000e5bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fdd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD1 17368 bytes
SHA-256: 25f84e6e77fd173681c3c9205e9a0c275815504474a79f2cae794e7e07cd8ce9