Malicious PDF — malware analysis report

Static analysis result for SHA-256 e15ac396a02d503a…

MALICIOUS

PDF

74.1 KB Created: 2021-09-25 13:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: eb9343f9dc246384a8021ea4da59ce9b SHA-1: 578e782dd6b2f0b936aa9e76aadba97328f291cc SHA-256: e15ac396a02d503a4e7b03546a660a8f976c461918371e574370f579e1e21452
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many of which point to external resources, with a high-risk heuristic indicating a link farm on disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1612f55781bb39---basajufituturuzixigevel.pdf In PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/46801355508.pdfIn PDF document text
    • https://profesa.net/userFilesfile/zolurawi.pdfIn PDF document text
    • https://0924055971.com/uploads/files/202109022209493606.pdfIn PDF document text
    • http://mirsistem.com/depo/sayfaresim/file/wezubasawi.pdfIn PDF document text
    • https://www.hkfew.org.hk/ckfinder/userfiles/files/jekud.pdfIn PDF document text
    • https://mashtalkandil.com/userfiles/file/19704189932.pdfIn PDF document text
    • https://vleek.com/uploads/files/dowefiritik.pdfIn PDF document text
    • https://cosonnguyenthanh.vn/webroot/userfiles/files/67821647319.pdfIn PDF document text
    • http://veewood.com/file_media/file_image/file/70612682690.pdfIn PDF document text
    • http://haokunchem.cn/upload/files/vebodox.pdfIn PDF document text
    • https://www.moxiclear.com.au/application/third_party/ckfinder/userfiles/files/32022938917.pdfIn PDF document text
    • http://0225674989.kad.tw/kads/ckfinder/userfiles/files/85735958262.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/52051871968.pdfIn PDF document text
    • http://sintellect.ru/Repository/file/77483012284.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/21977838572.pdfIn PDF document text
    • http://scro.ru/pic/file/10341092762.pdfIn PDF document text
    • http://www.ambatownship.com/ckfinder/userfiles/files/damofoxa.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/wewezazomuvomuwezep.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/28800326332.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/86162587065.pdfIn PDF document text
    • http://fabtur.ru/upload/files/67420463902.pdfIn PDF document text
    • https://hoya.hr/UserFiles/file/jadur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=sun+and+moon+casino+game+for+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_off0000b7d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7D8 18792 bytes
SHA-256: 2b70d404887d81b9fd42985ce160fc2ba94abd6e1a82331e8fed329c0cb68ae2
font_01_sfnt_off0000e7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FC 10852 bytes
SHA-256: ca558d7717463fd1e0abee102b0cfdc812725b200752b715e9d9ad446eb6e409
font_02_sfnt_off000100c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1