Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ff9c8cd127dea2…

MALICIOUS

PDF

81.2 KB Created: 2021-09-05 07:54:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 467f397f1cf1e3e715803e70d64a1f48 SHA-1: 3f779a67a56735428f5fb5fb2ce767503e47ada3 SHA-256: 99ff9c8cd127dea2ff88cb2fa689f18ced7faa7656bc331c38ce93d879e944af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, suggesting a link farm designed to distribute malicious content. ClamAV and ML classifiers identified this PDF as malicious, specifically flagging it as a phishing trojan. While no scripts were directly extracted, the nature of the embedded links and the detection signatures indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c916dc8a31c---93985820886.pdf In PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210725_214839.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/4935936641.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b04d9ce7d80---56096212627.pdfIn PDF document text
    • https://ovistar-dz.com/ckfinder/userfiles/files/59059274208.pdfIn PDF document text
    • http://aytekinpolatel.com/image/files/tukizasabowisosa.pdfIn PDF document text
    • https://eastmangroupllc.net/ckfinder/userfiles/files/831681534.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/82851185a642b7eb612e776104dc10ce/lupati.pdfIn PDF document text
    • https://10playsolutions.com/clients/softklk/documents/_articles_/file/bubimetaroxujanom.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609408cd79b04---32769051919.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/1f18da282805fbe944d1277c9cfc930d/30873315806.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f853daa5fa---87021694633.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610aff4a8e0c9---davedaf.pdfIn PDF document text
    • https://kocarbonag.com/luutru/files/fovosakofupo.pdfIn PDF document text
    • https://printjet.pl/pliki_user/File/tuxuzinodegaberatalako.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/3938016396.pdfIn PDF document text
    • http://ngor2-3.com/file_media/file_image/file/lotagozuxexemizapow.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/83f02f6ba1c35a0b654181359ed46692/30926082544.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160864f2286510---42069533292.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/xilasijodukexavat.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/b01100e948a3a547559fcac749c2a4c6/vupujaturor.pdfIn PDF document text
    • https://ksmt.edu.np/assets/ckfinder/userfiles/files/kibasolugamazelovuzubeje.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/eers9mj3k2nc866g100gmq2g75/lesavoni.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/33636554261.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/75e0df74ac60af6545984513516d65d1/5694286615.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=tamil+story+books+with+pictures+pdfPDF 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_off0000d2e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E2 18868 bytes
SHA-256: fc33fcdaae266367f1f0b22e6df332bc0eba24f9de8b4883a713d97bd8d7f238
font_01_sfnt_off00010439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10439 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C50 11276 bytes
SHA-256: f4e7c1600ea2a920ac7c03134b5bc1e4dc619b8ce5f0bd7a3ded061bcd1aa931