Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec3ebfa11047d505…

MALICIOUS

PDF

80.7 KB Created: 2021-09-20 14:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 843ebd3c4ac58bf25d847be1534bb98b SHA-1: 10a2e21213877d96a33c08bf2381d4bfe45790b3 SHA-256: ec3ebfa11047d505e15a70e8791a1424c9e73355fe9868ca171d526e788d6e93
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. Heuristics indicate it functions as a link farm with numerous external URIs pointing to disposable hosting, suggesting a phishing or malware distribution attempt. While no scripts were directly extracted, the PDF structure and numerous embedded URLs strongly suggest an intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/ec1a1bc7b7d8a3e72b3a9fb27118b991/vafikifuj.pdf In PDF document text
    • https://dafelia.com/files/jexubuxoriforimazagid.pdfIn PDF document text
    • http://pololanna.com/user_img/files/19472999964.pdfIn PDF document text
    • https://datxeninhbinh.com/data/dulieu/files/23190276586.pdfIn PDF document text
    • http://thaiboxes.com/piceditor/file/77206668411.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/tojetinefiliwisaxowov.pdfIn PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/35281132946.pdfIn PDF document text
    • https://laps.pl/userfiles/file/24099844836.pdfIn PDF document text
    • http://snieznik.pl/userfiles/file/6243770745.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/dizusosija.pdfIn PDF document text
    • https://petribax.com/userfiles/file/11361911206.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/duvimikobeda.pdfIn PDF document text
    • http://35ct1.com/images/ckImageFiles/files/41017543000.pdfIn PDF document text
    • http://siblom.ru/files/upload/file/guzanolataluzubuwodutag.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/30481407990.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/35992675767.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/gipodekujabijewewitaji.pdfIn PDF document text
    • https://valve-toho.com/userfiles/file/matak.pdfIn PDF document text
    • https://ta-taiwan.com/app/webroot/userfiles/files/25519845462.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/keparemaseraninelarike.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/sasilopasinag.pdfIn PDF document text
    • https://treasurehunterdetectors.solar-ovens.net/ckfinder/userfiles/files/85334436959.pdfIn PDF document text
    • http://vinabomi.com/uploads/userfiles/file/98288524837.pdfIn PDF document text
    • https://dehayemek.net/upload/ckfinder/files/84121809115.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=microsoft+internet+explorer+for+android+phonePDF 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_off0000d691.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD691 17580 bytes
SHA-256: 1e09a5a52889cccf691ddb3779d64d9211de6c952c3834b6eefeacc74860a4ac
font_01_sfnt_off0001049f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1049F 10812 bytes
SHA-256: 845fa19da6bae67ec341d8872202c280525cb806afcbe5abf4dcca6fd29c9262
font_02_sfnt_off00011d87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1