Malicious PDF — malware analysis report

Static analysis result for SHA-256 c028fd6a235745b5…

MALICIOUS

PDF

79.0 KB Created: 2021-09-13 02:59:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 03d27525932116b951d7164abd104eaa SHA-1: ffc99b0190a4eda786b92488e9d6e0019702d63b SHA-256: c028fd6a235745b55cc927fce83414b4efeb3682767ad3c337fa5e13de1805a8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains hosting other PDF files. This suggests a link farm or SEO poisoning attack designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://reaga.net/js/ckfinder/userfiles/files/54186303124.pdf In PDF document text
    • https://tomorrowhubs.com/upload/users/files/96490961503.pdfIn PDF document text
    • http://dc-42351dc5a6b3.prshots.es/uploads/userfiles/1630713287/files/bevekepikisalawovorebapu.pdfIn PDF document text
    • http://tottazo.com/userfiles/file/bapamalezem.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-9-5/20210905135914308219.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370eee4e085---85612659812.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/wukololeridaramokog.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///bekik.pdfIn PDF document text
    • https://moveo-sport.pl/userfiles/file/jefodituzojekapo.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/62391360796.pdfIn PDF document text
    • https://rowsontw.com/shopadmin/upload/files/fibutogubosunabizapesa.pdfIn PDF document text
    • http://bratislava.topenglish.sk/app/webroot/gallery/files/99314615806.pdfIn PDF document text
    • http://moveworldtogether.com/datas/files/besotanitodukizumadanoze.pdfIn PDF document text
    • https://locktactyuma.com/userfiles/file/61301070933.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/9009809924.pdfIn PDF document text
    • http://oilspecchem.com/files/99177146130.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/1302031172.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202109051000316540.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210901163049709577.pdfIn PDF document text
    • http://namngonviet.vn/user-/files/75188743486.pdfIn PDF document text
    • https://palezieux.com/ckfinder/userfiles/files/xevefuzet.pdfIn PDF document text
    • https://discovercefalu.it/_data/images/file/xuwano.pdfIn PDF document text
    • http://daugiavanthienphuoc.com/media/ftp/file/8277566694.pdfIn PDF document text
    • http://thibidi.vinadesign.info/uploads/images/files/biwedutaza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=kali+linux+download+apk+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_off0000cfc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC7 10464 bytes
SHA-256: 80649df3148dd177c16a74a8a67bceb53e83651e755784be727a02191b6a7b45
font_01_sfnt_off0000e799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE799 18136 bytes
SHA-256: eea3ef917039b488f4ba4889a193f1aefbea57965f93039ba57741eba55feadd
font_02_sfnt_off00011639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11639 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1