Malicious PDF — malware analysis report

Static analysis result for SHA-256 f838aeee08c28b30…

MALICIOUS

PDF

81.3 KB Created: 2021-09-17 06:08:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3875e101c9930390ef341b818605462f SHA-1: 21ca2d1b330163527194d1817bb3ffc90c49ebef SHA-256: f838aeee08c28b30e3b2ef9c55b15beff5f1297c84fc8df8c1b411f141ae5b3e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm directing users to numerous external URLs. The presence of embedded URLs and the PDF's structure suggest it is intended to redirect users to potentially malicious sites, likely for phishing or to download further malware. No scripts were extracted, but the overall behavior points to a common phishing or malware distribution tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pixomot.ru/uplcv?utm_term=android+clock+wrong PDF link annotation
    • http://swvocal.com/data/se2/file/wuwixi.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/47533869907.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efa3dd03cf---gepuwuliguba.pdfIn PDF document text
    • http://fuku-zou.com/userfiles/file/25250723512.pdfIn PDF document text
    • http://suarezbeltran.com/aym_images/files/20164710679.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/40544074162.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/kunopotoxal.pdfIn PDF document text
    • http://mebco.ru/images/file/5491148878.pdfIn PDF document text
    • http://perchegouet.com/ckfinder/userfiles/files/36369189637.pdfIn PDF document text
    • http://kledingindex.nl/images/uploads/zazovi.pdfIn PDF document text
    • http://creativecoms.net/userfiles/file/36537813138.pdfIn PDF document text
    • http://sandlnae.com/data/editor/file/linogobonuzo.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/58192440881.pdfIn PDF document text
    • http://icbiz.ru/userfiles/file/fufonebiboriz.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/18039042057.pdfIn PDF document text
    • http://ms-beauty.com/ckfinder/userfiles/files/62403249689.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/46217314975.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/gotaraduv.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/53154445311.pdfIn PDF document text
    • http://habitat3.eu/userfiles/files/fajuxopolugupe.pdfIn PDF document text
    • http://stroyindustry.com/userfiles/file/7671020144.pdfIn PDF document text
    • https://ever-progress.com/upload/files/43250358442.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/17658301878.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/161346e6fae5df---47569359231.pdfIn PDF document text
    • https://n-vv.dk/userfiles/file/20561105753.pdfIn PDF document text
    • http://fazekaskozpont.hu/images/upload/file/52085462480.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nutumowubivawezopemetu.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_off0000db68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB68 17928 bytes
SHA-256: 1db4433d950b75b5916ea7c64205bf5ce29c5192cde4333598662fae35ca8c71
font_01_sfnt_off0001097d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1097D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012194.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12194 10144 bytes
SHA-256: d6dede9b2c94bb9a3998a40d6506decc39c8d463e88e0dcc0ebf15f85ef83dbb