Malicious PDF — malware analysis report

Static analysis result for SHA-256 c405977a3a6ca6d9…

MALICIOUS

PDF

71.1 KB Created: 2021-09-01 06:04:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f41ddb7da99d334013850ac7de79508d SHA-1: 77a809747b4a53f478adb1b685af6e4bbae0e1d7 SHA-256: c405977a3a6ca6d9e9761f8ebfa5d973d0965f7b525a439372ebac16c33a2f65
156 Risk Score

Malware Insights

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

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 many embedded URLs pointing to potentially compromised or disposable hosting. The primary purpose appears to be directing users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16071b79dc8a28---83452854025.pdf In PDF document text
    • http://ngocvietbungalow.com/upload/files/nopikofudemaneli.pdfIn PDF document text
    • https://carlojans.com/cms/file/boxipazajagasagebe.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/5iktvg8eoboqoh71lkc18bgim0/fudilefugapazazusipaxuw.pdfIn PDF document text
    • https://monographie.com/ckfinder/userfiles/files/lofasofuzu.pdfIn PDF document text
    • https://guapa2.com/admin/fck/file/xakisul.pdfIn PDF document text
    • http://romengo.com/ckfinder/userfiles/files/23707634661.pdfIn PDF document text
    • http://kbchina.de/upload/mogaworage.pdfIn PDF document text
    • http://cambresisemploi.fr/ckfinder/userfiles/files/mavozejikijote.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/744a6891f656a19cd8ee6dd870aca431/55581055719.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/67772364182.pdfIn PDF document text
    • http://cuspsurgeons.com/userfiles/file/76133307808.pdfIn PDF document text
    • http://citygclub.com/ckupload/files/sewajomuzupawejibel.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/kuvitakamuloreviduzu.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/43382891667.pdfIn PDF document text
    • https://argumentua.com/i/file/rosupokitexowujuxefu.pdfIn PDF document text
    • https://eastmanllc.com/ckfinder/userfiles/files/zesaragezox.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/lagizizifizif.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a054cfc895a---sasum.pdfIn PDF document text
    • https://ev-owners.jp/userfiles//files/funofufeb.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/zabewagerovugogus.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/77547174188.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=double+dimensional+array+in+javaPDF 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_off0000b638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB638 10864 bytes
SHA-256: 65145eed3181be8b199a87fa76b8d32d3c818340b882af60a1b5d2ba12ce7560
font_01_sfnt_off0000cf30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF30 15384 bytes
SHA-256: 1bd03489026189b575e6143f2cf6343ef09d605a9e59e176be63ea6591804981
font_02_sfnt_off0000f652.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF652 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1