Malicious PDF — malware analysis report

Static analysis result for SHA-256 7043621a8c441403…

MALICIOUS

PDF

79.1 KB Created: 2021-09-16 08:00:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e4dd7738f9f2bc6d0a08928c5034f43c SHA-1: abd76a6a99c774c774b898555ff2a151ed4cd4dd SHA-256: 7043621a8c44140351e3452de0a7ae006a325d263c71248cfc58b233fdfd81d1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple external URIs and link farm heuristics indicates an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.phuongdonggolf.vn/app/webroot/uploads/files/zuruvokunexusimo.pdf In PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/q98i3fmhurnh8d1lub62nbi228/rituzajazumolifojavujufi.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/jasojuwafubibowalo.pdfIn PDF document text
    • https://nbc.com.vn/ckfinder/userfiles/files/vubupozupa.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/11399150173.pdfIn PDF document text
    • https://bushregenerators.biz/userfiles/files/96754300521.pdfIn PDF document text
    • http://norilskgu.ru/userfiles/file/norakafog.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/28309846233.pdfIn PDF document text
    • http://ckudzcssffhhj.handysociality.com/upload/files/mugivimirizufidit.pdfIn PDF document text
    • http://axi-hohenstein.de/userfiles/file/sajezavonexodonulefupotag.pdfIn PDF document text
    • https://menuiserie-sainte-anne.fr/userfiles/file/widonojezeposati.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16142cdc8a82e1---68986602131.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413e5fa8eb0---72471019644.pdfIn PDF document text
    • https://grouptm2.com/contents/files/xugobaxabifujatowubarevoj.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/85901001777.pdfIn PDF document text
    • http://rrbrentacars.com/files/others/97992485133.pdfIn PDF document text
    • https://xn--espaoldetalca-lkb.cl/var/www/html/upload/file/78814991421.pdfIn PDF document text
    • http://ayurveda-shiatsu-qigong-nice.com/upload/files/42694375558.pdfIn PDF document text
    • http://vektorma.ru/uploads/assets/file/16048789700.pdfIn PDF document text
    • http://cuacuontoanthang.com/media/file/64308844024.pdfIn PDF document text
    • https://icbacademy.com/upload/files/54853863940.pdfIn PDF document text
    • https://lecourbe.dk/userfiles/file/vavunigavojaxabuxuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=what+to+write+in+an+email+when+sending+a+cover+letter+and+resumePDF 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_off0000cfdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e7ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EF 17436 bytes
SHA-256: 202fdcc2162c144207f8380cfc0f7d7debf23c7139af4b08a9f0c943232595ec
font_02_sfnt_off000114ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CE 11064 bytes
SHA-256: 8285dd4cba9fafbbe95a128657dac4e5e241cfe05950cd8aa38da992446dccdd